Nitrogen And Other Things

[daizeUK]

I do not believe you did. If your API test kit reads .25 that is ppm of Total ammonia ions. However those studies do not measure ammonia on that scale- they read ammonia-n. We have touched on this before. What it means is one needs to convert the API reading into its lower ammonia-n equivalent. So when the kit says .25 the ammonia-n is .20. Using a plain old ratio or .2/.25=.8, so your .01 of NH3 is really .008. or you could just change the .25 ppm to .3125 ppm.

 
Okay, the chart has test readings in units of ppm NH3 rather than NH3-N so I just assumed it meant ion.
  

Secondly, you are still ignoring the time factor. You equate keeping tilapia fingerlings for 75 days in ammonia to keeping larger fish in it for a week or two, comparing apples to oranges basically.

 
The study dissects the fish after 75 days to investigate accumulated effects.  The damage would begin to occur at some unspecified time before 75 days.  It doesn't mean that you can keep fish in ammonia and they'll be perfectly happy until the 75th day when they suddenly get sick, so it makes sense to play on the safe side and assume a shorter time period.
 

Moreover you seem to have missed the information in the lines you quoted regarding the Tilapia aurea study it said the damage occured in fish exposed to both a non-lethal and then an acute dose. .25 ppm of total ammonia ions does not translate into an acute dose. So you have compared apples to oranges again.

 
My only point was that acclimating fishes to ammonia might increase their chance of survival but does not mean they do not suffer from it, in response to your suggestion that acclimating fishes might be considered a good thing.
 

Finally, how many people keep trout?  ....I could single out the toadfish....

 
I'm not sure what your point is, I haven't quoted any sources on trout.  Your original reference was based on a study of death rates of salmon, which I'm saying is not a good benchmark.
 

But lets consider for a moment the current state of fish keeping. In almost any part of the world where there is internet access any budding fish keeper should be able to stumble across the information regarding fishless cycling. And most of them should be able to find some source of ammonia they can use. So exactly why would anybody choose to cycle with fish? They know if they are not careful they might harm or kill fish. So it seems to me those folks are pretty much making a conscious choice to take that risk if they go with fish in cycling.
 
I would go so far to argue the the primary reason a fish in cycling or fishless cycling encounters problems is the result of over zealous behavior on the part of the fish keeper. And I would further argue this is more often than not being caused by incomplete and/or improper advice being followed. For example, using too many or the wrong type or age of fish in a fish in cycling. This is slow process which needs to be done with as few and as hardy fish as possible. Most folks do not hear this enough.

 
You only have to look in the New Freshwater Tank section to see that the majority of fish-in cyclers are first-timers who have bought fish on the recommendation of their LFS and they come to the forums asking what to do because their guppy is belly-up and their children are in tears about it.  They need advice on how to handle that situation, so you can't tailor advice assuming that your target audience are well-informed and have chosen fish that they either didn't care about, or were chosen especially for their hardiness.
 

I would point out that the article in the Beginner Section on this site on cycling with fish says nothing about which fish or how many fish one should use at the outset of a fish in cycle. It makes no mention of how the API test kit measures even while saying it is very popular with folks here. It makes no mention of NH3 vs NH4+. If one really wants to know what harm ammonia may be doing, they should be told to use SeaChem's ammonia kit which can measure NH3 directly no matter what dechlor is in use.

 
I agree with you, however I also believe that it is important not to overwhelm newcomers with too much information from the start.  Getting into fish-keeping can be overwhelming enough as it is and most people would probably be completely put off by having to revise high school chemistry at the same time!  The information should definitely be available, but it needs to be presented in a more newbie-friendly format.
 

So here is my next question. If you want to make the argument that one must blindly change water at .25 ppm on an API test kit when cycling with fish in,

 
I am disappointed.  I thought I had made it clear that that I was suggesting that high-pH tanks may benefit from water changes at 0.25ppm after considering other factors.  I haven't argued for blind water changes anywhere. 
 

can you show me research which shows what ammonia levels for what exposure times cause irreversible harm to zebra danios or most barbs (for warm water) or goldfish (for cool water)? These are the most commonly suggested ones for fw fish in cycling (I believe damsels or mollies are suggested for sw tanks?).

 
Why irreversible?  Who says that the person seeking advice about their fish-in cycle is not concerned about temporary harm to their fish?
 
I'm making the same points over again now, so I think that this discussion has run its course from my end.

 

[TwoTankAmin]

daize it is hard for me to have a back and forth exchange with you if you can not remember what you have said or if you make points and then contradict them.
 
You said:
 

I'm not sure what your point is, I haven't quoted any sources on trout.

 
Oh yes you did. Please see your post above dated  25 January 2013 - 05:19 PM and numbered post #12 in this thread where you quoted:
 
"Kirk and Lewis (1993) reported that the gills of rainbow trout exposed to 0.1 mg/l ammonia for 2 h exhibited deformation of the lamellae."
 
How can I respond when you say things like that?
 
I am going to give this one more try. You posted above that the tilapia damage was evident after 75 days and then suggested that there is no way to know when that damage may have occured. Well maybe this study will help clarify things for you. It is another study of tilapia:
 

The UIA no-effect levels (NOEL) calculated based on the methods of Tomasso (1994) corresponded to 0.131 mg/L UIA at 24 and 48 h, 0.120 mg/L UIA at 72 h, and 0.088 mg/L UIA at 96 h. These values show the maximum UIA  concentrations at which the UIA would have no long-term effects on growth or survival. At 30oC and pH of 7.6, these NOEL correspond to TAN of 4.2 mg/L at 24 and 48 h, 3.9 mg/L at 72 h, and 2.8 mg/L at 96 h, respectively.  Though UIA concentrations in aquaculture systems may not reach the LC50 concentrations found in this study, they may rise above the NOEL values and affect the long-term growth and survival of the Nile tilapia.

From http/digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1536&context=usdaarsfacpub
 
So this study shows that exposure for 4 days at a level of total ammonia nitrogen of 2.8 ppm (which on the API kit would read about 3.6 ppm) and results in .088 ppm of NH3, have no long effect on either growth or survival (i.e. exposed fish live just as long and grow just as much as unexposed fish). This would seem to fly in the face of the .25 ppm total ammonia and .01 NH3 exposure levels you state cause harm. However what that 75 day study does seem to support what I have been saying. That the time factor is a crucial consideration and that lower ammonia level exposure for longer periods is likely to be as or more harmful than higher level exposure for relatively shorter periods. There was one difference between the 75 day study and this one. The 75 day study used much younger smaller fish. This would also support my point that folks who cycle with fish are normally not using fairly young fish but are using more mature fish than that. So the 75 day study is less applicable in that respect.
 
One of the more interesting aspects of the study I just referenced involves the second part of it. the goal was to determine if fish exposed to the effects of ammonia at different levels would be more susceptible to infection from Streptococcus agalactiae. They injected the fish with this and then compared the effects on the control group vs the ammonia exposed groups. Now we all know that stress normally will reduce the ability of fish to fend off disease or to heal from damage. So one would think that the exposed fish would be more susceptible to the infection than the control fish. But as Table 4 of the study shows and what the researchers said was:
 

Mortality patterns among control and un-ionized ammonia (UIA)–exposed Nile tilapia challenged with Streptococcus agalactiae. Tilapia were injected intraperitoneally with 750 colony-forming units of S. agalactiae per fish after the
exposed groups were held under increased UIA conditions for 24 h. Following challenge, fish were monitored for 21 d. No significant differences in mortality patterns were noted between groups during any of the two experiments.

 
So there is evidence that short term exposure for significantly higher levels of ammonia then the .25/.01 ppm levels for TA/NH3 does not change the ability of the fish to fend off this desease. I am a patient person. I am willing to wait for anyone to show I am incorrect in my belief that an ammonia reading of 25 ppm on a salycilate test kit reading total ions is not an immediate cause for alarm or corrective action in almost any instance during fish in cycling. I also await scientific evidence that the resulting increased exposure time to a lower ammonia level than that .25 ppm is not a more damaging alternative. What does the ammonia test kit read if one's actual TA level is .10, .15  or .20 ppm?
 
Finally, fish in our tanks get harmed regularly. They bash into the glass, they get exposed to dirty water when we miss water changes, they may run into pointy sticks or sharp rocks. They scrape themselves trying to squeeze into tight places. Most times these things do not do permanent damage. But if folks are so intent on preventing any and all short term discomfort to fish during a fish in cycling, why are these people not also suggesting we wrap rock and wood with padding, that we pad the glass, that we all get sophisticated automatic water change systems to prevent dirty water, that we don't have any small caves or tight places in tanks? I have lost way more fish to this sort of things than to low level ammonia exposure for a short term during a fish in cycling.

 

[daizeUK]

Lol apologies about the trout reference.  It was a small note embedded in the tilapia study and I was paying more attention to the duration of exposure than the species of fish.
 
I'm just not sure that it is worth trying to continue a scientific debate when our interpretation of the results seem so incompatible.  It's just going to turn into an argument on ethics.  For example, you're now justifying deliberate ammonia exposure because fish bash their noses into the glass occasionally... I'm not even sure if you're joking.  My kids fall over and scrape themselves all the time, I don't wrap them in cotton wool, but that doesn't mean I'd be happy to let them breathe noxious fumes.
 
I'm fully prepared to accept that I didn't choose the best study and I'm sure it has flaws, but to be honest you have quoted unsuitable studies yourself.  We could probably find a better one but we have different ideas about what constitutes valid evidence.  I'm looking for studies on gill hyperplasia and minor temporary damage while you're quoting studies on survival rates and growth inhibition.
 
I think at this point I will simply try to remind you that you are proposing guidelines that will potentially be taken as gospel by a wide range of people under different circumstances, those guidelines are based on your beliefs of what constitutes an acceptable level of damage to the fish which is not necessarily representative of the beliefs or wishes of everyone who reads your advice.
 
 

I also await scientific evidence that the resulting increased exposure time to a lower ammonia level than that .25 ppm is not a more damaging alternative.

 
I'm not really sure what you're waiting for.  In post #15 you said:
"Dosing too much ammonia too often will usually slow a cycle not speed it up. Yet folks are dumping ammonia into tanks willy nilly and then posting their cycles are stalled or are taking way way longer than they should. And this is reinforced by those who categorically state the bacteria will die off rapidly if not fed any ammonia. The beginner often takes this to mean dose more often."
 
On the one hand you are suggesting that lowering the ammonia will make the cycle take longer, on the other hand you claim that adding ammonia will not speed the cycle up.  From what I understand from reading and experience with my own fishless cycle, exposing nitrifying bacteria to a lot of ammonia will not make them multiply any faster, indeed it can inhibit them as you rightly said.  So why all the confusion about exposing fish to lower doses for longer?  The aim is to make the bacteria process ammonia at the same rate as the fish produce it, very low levels are needed to make this happen.
 
Even if removing ammonia did slow the cycle down, I cannot think of a single general example where short exposure to a high dose of toxin is preferable to a proportionately lower dose over a longer time period.  The key here is proportional, if the duration of exposure is excessively disproportional then a short higher dose may be preferable to, say, years at a lower dose, but I don't think that's what is happening here.  That's not based on any scientific evidence, just common sense, so feel free to pick me apart if you like.

 

 

[TwoTankAmin]

I am sorry if I did not make it clear enough. There is a difference between cycling with fish or without. When cycling with fish one should not let the the ammonia levels get anywhere near 4 ppm  In fishless cycling one should dose to a max of 4-5 ppm TAN-N and wait for it to go to 0 before redosing. I was trying to point out that in fishless, folks are dosing willy nilly.
 
My points regarding fish-in cycling are from a completely different perspective. Perhaps I can clarify them.
 
1. When one cycles with fish they have made an intentional decision to expose fish to some level of ammonia and nitrite. Even if the had no intention of doing this and were "tricked" into it by a local store, once the fish keeper becomes informed of the actual consequences, they have an alternative in many cases. This can range from how they handle the balance of the fish-in cycle to removing the fish to a Rubbermaid and keeping them in this uncycled container with heat and air and doing regular water changes while finishing up their cycle w/o fish.
 
2. If one if going to continue with the fish in cycling route, I see two overriding concerns when it comes to how much and for how long one exposes the fish to ammonia and nitrite. And this boils down to two issues. How much ammonia or nitrite will cause permanent harm/damage in absolute terms. This must be avoided. But then the next question becomes knowing what levels of ammonia or nitrite can the fish handle and not cause any permanent harm. So what is the difference between exposing fish to .25 ppm TA for a few days vs a few weeks? What is the difference between that .25 for a few days vs 1/2 that much (which you cant measure on the API test kit) for a few weeks?
 
3. What is known is that even lower levels of ammonia can cause harm, often permanent damage, when the exposure time is extended. But they illustrate the dilemma. We know that stress reduces the ability of a fish to fend off illness, to be its healthiest etc. When one has to perform lots of water changes, like every day or two to hold down ammonia levels, what harm is this potentially causing fish in terms of stress? New fish, in a new tank exposed to even low levels of ammonia and/or nitrite are a lot more likely to be stressed by the water changes than fish living for months in an established tank. Moreover, these fish in  fish-in cycle have recently been shipped to a store, kept in an over crowded shop tank, been underfed, may have been picked on and then were netted, bagged, transported etc. again.
 
4. Most of the research into toxicity breaks down into a few areas. The most obvious is the determination of what levels kill fish. Sometime these studies will also look at what levels cause no harm and/or if any harm is permanent or reversible. Some will look at low levels of exposure and what effect that may have over the longer term. But the thing to bear in mind is that most of the studies do not give a hoot about fish in aquariums. They are concerned with aquaculture practices or how to keep fish healthy during shipping. Or they may be concerned with studying the effects of the nitrogen products in the wild from fertilizer or sewage runoff etc.
 
5. Finally, who can say with any certainty that fish feel pain or what makes them suffer? What can be measured is damage to the fish- which usually means killing it in the process- or if that damage heals subsequently. What can be measured is growth rate. Damaged fish should not exhibit normal growth rates and behaviors, which is why these things are relevant to the studies. But lets bring this down to a more simple level- exactly how does anybody know if a fish feels pain at any given time? How can anyone say that .25 ppm of TA measured on the total ion scale harms a fish (even if it is not permanent damage)? How do you or anyone else know this? I am not even sure lab research can answer this question.
 
It seems to me that the overriding goal in fish-in cycling is to have it go as rapidly as possible without causing any permanent damage to the fish. And in this respect it is relevant to know which fish are safest to use for a fish-in cycle because they have the highest tolerance for ammonia exposure. But it is equally important to know at what level ammonia becomes an issue one must handle vs one that should be tolerated. For me the .25 ppm level on the specified type of test kit is rarely ever that level based on everything I have read or done myself (the latter is only anecdotal evidence of course).
 
I think one of the things that doing the research should show is the ammonia (or nitrite) levels being used in the research are normally way way higher than what most would expect. I consistently see that almost no study concludes that .01 ppm of NH3 is the threshold for damage to anything but very young fish. The goldfish person who hosts the table with the yellow/red in the boxes puts the level at .03 ppm based on his personal experience and the Merck veterinary manual puts it at .05 ppm. And when we read the the goal is to have 0 ppm, this is not in regards to the short term cycling time in tanks but in regards to well stocked aquaculture facilities etc. An established fish pond or fish tank should both have 0 ammonia or nitrite because either of those things indicate an unexpected problem in the system.
 
In summary, when it comes to reading .25 ppm of ammonia in a tank using a salicylate kit and into which on is dosing Prime etc. is not a cause for alarm for numerous reasons:
 
1. The kit is overstating the actual ammonia levels.
2. The dechlor may be giving a false reading,
3. There is likely not enough ammonia present at this level to cause harm to fish over a short term (i.e. NH3 levels).
4. Reducing ammonia levels during fish-in cycling will also increase the length of the time it takes to complete the cycle.
5. I have not seen any proof that this level over short term (days of a week or two) exposure periods causes fish to suffer (i.e. be in pain).
 
My advice will always be to suggest that folks do not cycle with fish. If they do, get the fish out and finish the cycle w/o fish if you can. That means parking your fish elsewhere- whether with a friend, back at the store or in an uncycled Rubbermaid or other container doesn't matter as long as the fish are out. But short of that my goal is to complete the cycle as rapidly as possible while minimizing the potential to harm the fish. Nothing I have seen indicates that the .25 ppm TA level is the key number. In fact let me make me seem even worse by stating that in a lot of cases even .50 ppm would not require action (this would be based on the pH and temperature of the tank involved of course as well as what stage the cycle is at).

 

[daizeUK]

1. Is there really any benefit to moving fish to a separate environment while the original tank is cycled with ammonia?  Is there any evidence that a fishless cycle will happen faster than a fish-in cycle?  I can say that in my case, it would almost certainly not be!  Fifty days now without nitrites... that's a long time for fish to be stuck in a plastic box.
 
I think you are also overestimating the chances that a concerned person will return their fish to the shop after they realise their mistake.  The shop may not accept the fish, the new owners may already feel a sense of obligation to the animals, the children might cry etc.  None of these reasons have to make logical sense, but my point is that just because owners continue to fish-in cycle does not mean that they don't care about the fish.  Their values of how much pain they want the fish to suffer may be significantly lower than yours, you cant impose your personal judgement on them.
 
2.  Where are you getting these figures from?  0.25ppm ammonia for a few days versus half that for a few weeks... is this based on evidence from somewhere?  I have not heard any evidence to suggest that doubling the amount of ammonia during a fish-in cycle will dramatically increase the reproduction rate of bacteria.  Nitrififying bacteria are limited to a slow reproductive rate of around 12 hours anyway (off the top of my head) and as long as there is free ammonia for them to feed off I'm not convinced that doubling it will make them multiply any faster.
 
3.  I accept your argument that new fish will feel stressed and water changes is likely to increase that stress, however this must be balanced against the stress levels they experience from exposure to low levels of ammonia.  I am open to further evidence about this but my current perception is still that fish will feel sufficiently stressed from ammonia in high-pH tanks to warrant water changes.  The sort of research we need to determine this is low-level damage or irritation to gills, which is why I've been looking for studies in this particular area.
 
4.  If we are restricted to relying on research for commercial fisheries then it is important to make this clear when providing recommendations based on them.  It is misleading to say that fish will be fine at 0.25ppm ammonia when what we really mean is that fish won't die and are unlikely to suffer permanent damage as long as the exposure does not last more than a few days, however they may still be irritated and unhappy.  It is up to individual fishkeepers to decide whether they prefer to err on the side of caution or push their fish to the limits but they can't do that if they're unaware of the basis for your judgements.
 
5.  Oh dear, not this.  This debate is sinking to a pretty low point now.  I could point out that there is a lot of scientific evidence now to suggest that fish do in fact feel pain, but honestly I don't even care.  It's simple common sense logic that a complex species cannot survive and evolve without some perception of detrimental stimuli.  Whether they feel pain in the same way that we do is a different argument and I don't think particularly relevant.  The fact that they have some kind of awareness of damage suffered to their bodies is indisputedly evident and more than enough reason to avoid inflicting damage on them for humane reasons.  Even if you don't agree with me then I would have to say that using the argument that it's okay to inflict damage because they might feel pain but we don't know so let's assume they don't... well, I honestly don't understand the mentality of people who think like that.
 
Like I said, this is in danger of turning from a scientific debate into an ethical argument and there appears to be very little compromise on either side.

 

[TwoTankAmin]

Is there any evidence that a fishless cycle will happen faster than a fish-in cycle?
 
Of course it is faster when the determination if for how long from set up to being fully stocked. A fishless cycle allows for full stocking when completed. A fish-in cycling requires gradual stocking. Under all other things being equal, the fishless goes faster.
 
Their values of how much pain they want the fish to suffer may be significantly lower than yours, you cant impose your personal judgement on them.
 
I will not argue that fish are not capable of feeling pain. I will even tell you there are ways that can be determined and measured. But that is a far cry from saying that exposure to .01 to .02 ppm of NH3-N and the concomitant level of NH4+ causes pain. you are assuming it does, not showing any evidence it does. But if you do some research in fish and pain you will discover there are usually some behavioral cues that can be used. A report by a poster that they have .25 ppm on the API kit but the fish all appear to be fine is a far cry from they are in pain.
 
If you want to state that low levels of ammonia over short term periods causes pain in fish, I would ask you to provide any form of research to support this. otherwise it is merely something you think is true and nothing more.
 
Where are you getting these figures from?  0.25ppm ammonia for a few days versus half that for a few weeks... is this based on evidence from somewhere?
 
You are a pip sometimes daize. Here is what I asked you not what I claimed was true.

So what is the difference between exposing fish to .25 ppm TA for a few days vs a few weeks? What is the difference between that .25 for a few days vs 1/2 that much (which you cant measure on the API test kit) for a few weeks?

I was inquiring how you know that .25 ppm for some number of days was more or less harmful that a lower level of ammonia for a greater number of days. Remember it was you above who argued that even low level exposure for more time was bad based on the 75 dy fingerling study. I do not mind going back and forth, but you make it a bit difficult when you can not seem to remember what you or I have said in the process.
 
I have not heard any evidence to suggest that doubling the amount of ammonia during a fish-in cycle will dramatically increase the reproduction rate of bacteria.  Nitrififying bacteria are limited to a slow reproductive rate of around 12 hours anyway (off the top of my head) and as long as there is free ammonia for them to feed off I'm not convinced that doubling it will make them multiply any faster.
 
Who said it did? But it does. Here is a set of tables (Gig. 2) for research into AOB in soil. But its the best I could find for you fast. You will note that there are 3 ammonia loadings followed, one being the 0 control. Note in chart C that there are more AOB for the 7.5 dose vs the 1.5 dose. Look especially at day 7.

From http/www.ncbi.nlm.nih.gov/pmc/articles/PMC348910/o
Common sense should tell you that a colony can only grow to the size of the available food source. Not in that chart the both ammonia loadings produce neck and neck growth rates for the first 3 days and then they diverge significantly through day 7.
 
Almost everything you suggest is your feeling, your perception etc. You have yet to provide any sort of evidence for what you say. I believe I have offered much more science to support my position and almost no opinion at all. I suggest you do a bit more researching on the topics. Areas you might want to investigate include
 
How is the experience of pain in fish tested and measured.
What sort of behavioral changes can one observe in fish to indicate they are stressed and/or pain.
Effects of low levels of NH3 on fish over short term periods- a few days to a couple of weeks.
 
Finally, most newbies who end up with too many fish in an uncycled tanks do have all the alternatives as I posted. Just because a few may not doesn't make those alternative unreasonable. So to refesh your memory let me repeat what I did say.
 
The preferred course of action would be to remove the fish and finish cycling w/o them. Possible places the fish could go temporarily are back to the store, to a friends house, to a rubbermaid uncycled which one would do daily water changes on etc. I then said if none of that was possible then my goal is to complete the cycle as rapidly as possible while minimizing the potential to harm the fish.
 
So exactly where have I suggested at any point that fish be intentionally harmed? In fact most of what I have said was just the opposite. Let me summarize my original points as posted in this thread.:
 
-If you are using the API ammonia test kit (the one most often recommended on this site) you need to adjust your test result accordingly. Thus a reading of .25 ppm it is actually more like .20 ppm (based on the article linked to in the first post).
 
-But lets ignore this part of things for the moment and just look at .25 ppm of total ammonia and figure out how much of it is NH3. To do this requires knowing one's tank pH and temperature and then using a conversion chart or factoring chart to calculate the amount of NH3 present. The former is pretty simple and can be found here http/dataguru.org/...AmmoniaTox.html As you can see in almost every situation, NH3 will not be a problem.......... There is little need to do anything unless your tank parameters put you into the small red areas on the chart.
 
-But there are even more factors to consider. The first is which dechlorinator one is using and when one is testing for ammonia. If one is using the most common kits, they will also contain an ammonia detoxifier. This is typical of SeaChem''s Prime for example. "Under the conditions of a salicylate kit the ammonia-Prime complex will be broken down eventually giving a false reading of ammonia (same as with other products like Prime®), so the key with a salicylate kit is to take the reading right away." So what this means is unless that .25 ppm reading was obtained soon after adding the dechlor, the odds are you are getting a false reading. The .25 ppm is testing error and not ammonia being present.
 
- By lowering the total ammonia level when its at .25 ppm you are also extending the cycling time. So while you may be lowering the ammonia level you will also be exposing fish to a lower level for a more extended period. Now factor in that the ammonia nitrogen reading is .2 not .25 ppm and those red areas will almost vanish off the chart.
 
-Now it is one thing to want to reduce 10 ppm ot total ammonia to protect the fish and a totally different issue at .25 ppm. If one reads ,25 ppm on the way up, it is way too soon to do anything. If one reads .25 ppm on the way down, then there is almost never a need to do anything.
 
-Almost the only time an accurate reading of .25 ppm for total ammonia ions is a worry is when it is in an established tank where ammonia should always read 0 using common test kits.
 
Please show me where any of this is not true, where I said subject fish to harm or suffering etc.? Please show me where I said .25 ppm on the salicylate kit was 100% never an issue. Show me where you provided an answer to my question about reducing the ammonia level from .25 ppm on an API type kit to a lower level via a water change, meaning a longer term exposure to lower levels, is more or less harmful than the .25 ppm for less time. And since you introduced the pain issue, show me some evidence of what levels of ammonia exposure (NH3 and/or TA) for what short term period causes pain and/or physical damage that is not reversible and which impacts lifespan, general health etc. Oh yes please, can you offer evidence that whatever level below .25 ppm you are suggesting one go to does not also cause fish pain? I mean maybe one should not cycle with fish because the amount of ammonia and nitrite it takes, even if the kits cant detect them, hurts fish. Can you even say that is true or not?

 

[daizeUK]

Almost everything you suggest is your feeling, your perception etc. You have yet to provide any sort of evidence for what you say. I believe I have offered much more science to support my position and almost no opinion at all. I suggest you do a bit more researching on the topics.

 
Agreed.  I wanted to find some common ground on what kinds of research would be pertinent and to ensure that we had clear ideas about what our goals are before continuing any further research.  It disturbed me that recommendations were being based off studies of fish mortality and your arguments for what levels of suffering were acceptable for fish in a cycle seemed too high for my tastes.  If we have reached understanding on this then I'd also like to get away from the ethics and back to the science!
 

Where are you getting these figures from?  0.25ppm ammonia for a few days versus half that for a few weeks... is this based on evidence from somewhere?
 
You are a pip sometimes daize. Here is what I asked you not what I claimed was true.

So what is the difference between exposing fish to .25 ppm TA for a few days vs a few weeks? What is the difference between that .25 for a few days vs 1/2 that much (which you cant measure on the API test kit) for a few weeks?

I was inquiring how you know that .25 ppm for some number of days was more or less harmful that a lower level of ammonia for a greater number of days. Remember it was you above who argued that even low level exposure for more time was bad based on the 75 dy fingerling study. I do not mind going back and forth, but you make it a bit difficult when you can not seem to remember what you or I have said in the process.

 
Please don't make it personal, you have also forgotten things that I've said but I don't criticise you personally for it. 
Your phrasing did not make clear that the question was hypothetical and so I took it as indication that you had some definite knowledge of the duration of cycles at different concentrations of ammonia.  If you were pulling arbitary figures out of the air instead then this is exactly the sort of thing I would like to pin down and research further; exactly what effect does the concentration of ammonia have on reproductive rates of bacteria.  Knowing this would make subsequent research on effects of exposure durations much more valuable.
 

I have not heard any evidence to suggest that doubling the amount of ammonia during a fish-in cycle will dramatically increase the reproduction rate of bacteria.  Nitrififying bacteria are limited to a slow reproductive rate of around 12 hours anyway (off the top of my head) and as long as there is free ammonia for them to feed off I'm not convinced that doubling it will make them multiply any faster.
 
Who said it did? But it does. Here is a set of tables (Gig. 2) for research into AOB in soil. But its the best I could find for you fast. You will note that there are 3 ammonia loadings followed, one being the 0 control. Note in chart C that there are more AOB for the 7.5 dose vs the 1.5 dose. Look especially at day 7.
[...]
From http/www.ncbi.nlm.nih.gov/pmc/articles/PMC348910/o
Common sense should tell you that a colony can only grow to the size of the available food source. Not in that chart the both ammonia loadings produce neck and neck growth rates for the first 3 days and then they diverge significantly through day 7.

 
Thank you for finding this.  I need more time to look at it and I will have to come back to it later, just a few initial observations and musings which I will have to come back and think about;
 
1) These results are comparing an ammonia source which is dwindling to zero and then not replenished, versus a single large source which is not fully consumed within the time period.  This is not analogous to a fish-in cycle where ammonia is constantly being replenished by the fish.
2) Up to day 3 growth rates are identical.  This shows that bacterial reproductive rates are capped at its maximum and there is no benefit to exceeding ammonia concentrations required to reach this maximum growth rate.
3) After day 3 the growth rate slows down as ammonia concentrations decrease and the colony approaches maximum size to process the amount of ammonia that was provided.  This illustrates how the growth rate of bacteria in a fish-in cycle might be hindered after a water change, thus slowing the cycle down.
4) It appears at first glance that the growth rate of bacteria is not affected until ammonia levels drop to about half the initial concentration.  Could this be an indication that water changes of less than 50% might be of benefit to the fish without significantly affecting the growth rate of bacteria?  Need to look at this more closely.
 
I also find it interesting that the A-bacs show few signs of dying even after a further 14 days at zero ammonia.  This supports the idea that established bacteria can survive for a considerable time without food.  But why the dip after day 7?  If the bacteria can survive for that long without food then what causes that sudden die-off after the population reaches its maximum value?
 
One thing that is missing from this study is the effects of frequency of ammonia replenishment.  I'd love to see what the results would look like when more ammonia is added at regular time intervals for both low and high initial doses.
 

 Areas you might want to investigate include
 
How is the experience of pain in fish tested and measured.
What sort of behavioral changes can one observe in fish to indicate they are stressed and/or pain.
Effects of low levels of NH3 on fish over short term periods- a few days to a couple of weeks.

 
Agreed, although I would still argue that determining how fish experience pain is not a priority.  Since ammonia has visible physical effects on the fish (inflamed gills, reduced kidney & liver function) then these are the indicators I would use for the purposes of determining how much/long a fish can safely be exposed to ammonia.
 

Finally, most newbies who end up with too many fish in an uncycled tanks do have all the alternatives as I posted. Just because a few may not doesn't make those alternative unreasonable. So to refesh your memory let me repeat what I did say.
 
The preferred course of action would be to remove the fish and finish cycling w/o them. Possible places the fish could go temporarily are back to the store, to a friends house, to a rubbermaid uncycled which one would do daily water changes on etc. I then said if none of that was possible then my goal is to complete the cycle as rapidly as possible while minimizing the potential to harm the fish.

 
Alright.  I've not heard it suggested before that people should move their fish into a temporary container while they use ammonia to fishless cycle the filter.  If this is a workable and preferable solution then why isn't it suggested to newbies more often?  Generally once people have fish in their tank they are just pointed in the direction of the fish-in cycling guide.
 
It may be worth clarifying what conditions would be necessary to achieve this, i.e. the fish would require a seperate filter and heater in their temporary container.  The owner would effectively be conducting a fish-in and a fishless cycle at the same time, in the hopes that the fishless cycle would complete faster.
 
Is there some reason why the fish should be moved out while the tank cycles?  Why not simply put the filter and ammonia into the temporary container and let the fish remain in the tank?  Assuming that the tank is larger then the more water they have to dilute their waste, the better.
 
I am a little concerned that a fishless cycle is more likely to stall than a fish-in cycle, which could cause the whole process to take even longer than necessary if not done properly.  (Yes, guilty as charged.  I would be tearing my hair out right now if I had fish in a bucket waiting for my tank to cycle).
 

-If you are using the API ammonia test kit (the one most often recommended on this site) you need to adjust your test result accordingly. Thus a reading of .25 ppm it is actually more like .20 ppm (based on the article linked to in the first post).
 
-But lets ignore this part of things for the moment and just look at .25 ppm of total ammonia and figure out how much of it is NH3. To do this requires knowing one's tank pH and temperature and then using a conversion chart or factoring chart to calculate the amount of NH3 present. The former is pretty simple and can be found here http/dataguru.org/...AmmoniaTox.html As you can see in almost every situation, NH3 will not be a problem.......... There is little need to do anything unless your tank parameters put you into the small red areas on the chart.

 
I agree with everything except the interpretation of the red areas on the chart.  As I said from the start, these are based on mortality rates of salmonids and I would prefer to confirm those figures with other research before taking them as gospel.  The orange areas are not identified at all and could be completely made up for all I know.
 

-But there are even more factors to consider. The first is which dechlorinator one is using and when one is testing for ammonia. If one is using the most common kits, they will also contain an ammonia detoxifier. This is typical of SeaChem''s Prime for example. "Under the conditions of a salicylate kit the ammonia-Prime complex will be broken down eventually giving a false reading of ammonia (same as with other products like Prime®), so the key with a salicylate kit is to take the reading right away." So what this means is unless that .25 ppm reading was obtained soon after adding the dechlor, the odds are you are getting a false reading. The .25 ppm is testing error and not ammonia being present.

 
I think we need to be clear here.
1.  Any dechlorinator that removes chloramines will introduce ammonia into the tank, wherever the tap water contains chloramines.  I've tested this myself and I get about 0.20ppm total ammonia on the API test after dechlorination (this is with a dechlorinator that does not attempt to detoxify the ammonia).  So when using this sort of dechlorinator under these conditions there is very little point in considering a water change at 0.25ppm ammonia.
 
2.  We discussed the ammonia-detoxifying properties of Prime back in posts #6-8 but I am still not fully clear on this.  You say that "unless that .25 ppm reading was obtained soon after adding the dechlor, the odds are you are getting a false reading."  However I understood from your explanation in post #7 that Prime will detoxify the ammonia by converting it into a more complex substance which is harmless to fish but still digestible by A-bacs.  You then said that "During this period a salicylate ammonia test kit will still show that detoxified substance as ammonia, which they consider to be a false reading."   So I would take this to mean that a false ammonia reading will be present immediately after adding Prime followed 48 hours later by an accurate reading as the substance reverts to ammonia. 
 

Please show me where any of this is not true, where I said subject fish to harm or suffering etc.?

 
My point has always been that your charts do not promise that fish won't suffer.  You've since pointed out that owners must accept some level of harm to their fish when they start a fish-in cycle, followed by justification because they experience pain in their day-to-day exploration of the tank and finally questioning whether fish feel pain at all.  Perhaps you don't intend to suggest that fish-in cycling should be painful to fish, but your arguments and research sources have given that impression
 

Please show me where I said .25 ppm on the salicylate kit was 100% never an issue.

 
That's how people will generally read it unless we cover the cases where it may be an issue.  All I am trying to do is determine with certainty whether 0.25ppm may be an issue for high pH tank owners.  I agree that more research needs to be presented before this can be clarified one way or the other, I'm just concerned that without clarification it may be misleading to present generalisations to those with more extreme conditions.
 

Show me where you provided an answer to my question about reducing the ammonia level from .25 ppm on an API type kit to a lower level via a water change, meaning a longer term exposure to lower levels, is more or less harmful than the .25 ppm for less time.

 
I think this is key, I have run out of time right now but I want to spend more time and come back to this.
 

And since you introduced the pain issue, show me some evidence of what levels of ammonia exposure (NH3 and/or TA) for what short term period causes pain and/or physical damage that is not reversible and which impacts lifespan, general health etc.

 
I'm still confused why you keep using the term irreversible?  I've stated several times that I do not believe we can ethically ignore temporary pain and damage that will heal but you have not acknowledged this.
 

Oh yes please, can you offer evidence that whatever level below .25 ppm you are suggesting one go to does not also cause fish pain? I mean maybe one should not cycle with fish because the amount of ammonia and nitrite it takes, even if the kits cant detect them, hurts fish. Can you even say that is true or not?

 
I do agree with you to some extent that if you choose to do a fish-in cycle then you have to accept some level of discomfort and stress to the fish.  I'm not saying that pain can be completely eliminated from a fish-in cycle.  I've brought this subject up because your guidelines were based on research that was unconcerned with minor physiological effects on fish and so completely overlooked factors that we as hobbyists (rather than commercial breeders) may want to consider.  I'm looking for a compromise that does account for fish well-being.  My personal benchmark for tolerable fish discomfort are lack of physical signs of gill irritation.  If somebody else wants to argue that even this is too much and fish should not be subjected to any pain whatsoever then I fully support that, nobody is arguing that fishless cycling is not a superior option! 

 

[TwoTankAmin]

Lets revisit the assumption that any level of ammonia exposure that can show up on a test kit harms fish and the fact that you appear to be basing this conclusion on the Arizona Univ. site http/ag.arizona.edu/azaqua/ista/ISTA8/mohamedshreif12.pdf This was the one you suggested showed that .01 ppm of NH3-N was harmful to fish.
 
If you go back an reread it here is what you are going to find that should stand out:
 
1. The test subjects were fingerlings weight about 2/3 of an ounce. Very young fish are more susceptible than older fish. So there was already a predisposition for ammonia exposure to be more harmful to them than to more mature fish.
 
2. They measured the effects of 4 different concentrations of HN3-N over 75 days and then did the testing on a number of parameters. The concentrations were .01, .05, .10 and .15 ppm and a control was used with no added ammonia and which tested at .004 ppm naturally produced.
 
3. The first parameter reviewed was mean individual body weight. And here is the conclusion for that:

The statistical analysis of mean results indicated that the mean individual weight of Nile tilapia (O. niloticus) fingerlings showed no significant (P ≤0.05) differences between FBW of tilapia in the control (0.004mg/l UIA-N) and FBW ofthose exposed to (0.01 and 0.05 mg/l UIA-N). While, FBW of tilapia exposed to 0.1 and 0.15 mg/l UIA-N was significantly (P ≤0.05) reduced from the control. The results showed that the lowest-observable effect concentration on the FBW was 0.1 mg/l UIA-N .

So the conclusion here is that neither .01 or .05 ppm had a significant effect on body weight.
 
4. The second parameter was the mean body weight gain. And here is the conclusion for that:

Generally, mean body weight gain was significantly reduced in concentrations of 0.1 and 0.15 mg/l UIA-N compared to the control ones.

Note the insignificant difference at .01 ppm and the barely significant difference at .05 ppm
 
5. The Third parameter was the average daily body weight gain. And here is the conclusion for that:

It can be shown from the statistical analysis that there was no significant (P ≥0.05) differences between the average dailybody weight gain of (O. niloticus) fingerlings in the control (0.004 mg/l UIA-N) and of those exposed to(0.01 and 0.05 mg/l UIA-N).

Again, note  no significant effect at .01 and 05 ppm levels.
 
6. The fourth parameter was average food consumption and the conclusion:

Generally, significant differences were found between UIA-N concentrations (0.1and 0.15 mg/l) and control (0.004 mg/l ,P ≤0.05). While, the differences were not significant (P ≥0.05) between food consumption in the control and of those exposed to UIA-N concentrations (0.01 and 0.05 mg/l).

Once more the .01 and .05 ppm concentrations were not significantly different from the control.
 
7. The fifth parameter was specific growth rate, and here again are the results:

The statistical analysis showed no significant differences (P ≥0.05) between the control group (0.004 mg/l UIA-N) and groups exposed to(0.01 and0.05 mg/l UIA-N).

I am getting tired of typing over and over that at the .01 and .05 ppm concentrations were not significantly different from the control.
 
8. The sixth parameter was the feed conversion ratio. Look at table 6 (I can't reproduce it here) which shows no significant difference between .01, .05 and the control at .004 ppm
 
9. The seventh parameter was blood measurements (for Hematocrit value (PCV%)) and it concluded:

Generally, significant differences were found between the UIA-N concentrations 0.05, 0.1, 0.15 and 0.004 mg/l (P ≤0.05). But the differences were not significant (P ≥0.05) between UIA-N
(0.01 mg/l) and control ones (0.004 mg/l).

Here is the first time any significant difference was found at the .05 ppm level but still not at .01 ppm
 
10. The eighth parameter was the average hemoglobin concentration in the blood and trhe conclusion:

It can be concluded that there were differences in the average Hb concentration of (O niloticus) fingerlings at the UIA-N concentrations (0.05, 0.1, 0.15 and 0.004 mg/l). While, there were no significant differences between UIA-N concentration (0.01 mg/l) and control (0.004 mg/l).

Still not seeing anything significant for that .01 ppm level. And anemia is not that hard to reverse I believe?
 
11. The ninth parameter was the start of the histopathological studies which began with the gills and found:

Examination of tissues from Nile tilapia (O. niloticus) fingerlings after 75 days of exposure to (0.01 mg/l) UIA-N concentration showed, slight pathological alteration. The gills secondary lamellae showed mild vacuolation (Figure 2), mild hyperplasia of epithelium.

This is the first time any damage was show for .01 ppm and it is described as mild and it was after 75 days of exposure. I consider this only somewhat significant due to the time factor. No cycle takes 15 days unless it is badly botched imo.
 
12. The tenth parameter was tests on the kidneys. This showed:

Examination of tissues from Nile tilapia (O. niloticus) fingerlings after 75 days of exposure to (0.01 mg/l) UIA-N concentration showed marked hyaline droplet degeneration and swelling of renal tubules.

This is the second sign of any effect at .01 ppm and again was after 75 days of exposure. There is no indication if any of the "damage" reported at the .01 ppm level is either permanent or reversible nor how it may or may not effect the fish over their entire life after the 75 days. We have no input regarding any pain. What we can certainly conclude from this not to keep very young fish in .01 ppm of ammonia for 75 days. It doesn't help us to know the effects of only a 15 or 20 day exposure. And the trout study results mentioned don't really apply to fish one might have in a home aquarium. Trout are know to be very sensitive. The higher levels of ammonia were clearly negative in their effects.
 
13. The eleventh parameter they investigate was the liver and they found:

Examination of tissues from Nile tilapia (O. niloticus) fingerlingsafter 75 days of exposure to (0.01 mg/l) UIA-N concentration showed that some hepatic cells were vacuolated (Figure 12).

There is clearly some effect at the .01 ppm level here also. How serious or how permanent it is we can not tell from their description. Does it cause pain, is it reversible, does it effect lifespan can not be concluded form the data provided. The higher levels of ammonia were clearly negative in their effects.
 
14. The final parameter was the LC levels. But since you want to rule out that as an issue for dicussion, there is no point in looking at the results. It is interesting to note how high the concentrations are relative to .01 ppm.
 
15. The study reaches the following conclusion:

It could be concluded that Nile tilapia (O. niloticus) fingerlings with average weight 19.0± 1.0 g, were more suitable to culture at water UIA-N concentration of  0.01- 0.004 mg/l for optimum growth performance and survival rate than other water conditions.

 
Now a lab full of scientists doing hands on controlled research comes to this conclusion regarding very young fish. You disagree with that conclusion, but have not yet been able to provide other relevant research that would indicate otherwise.
 
But all of the above departs from the real topic at hand. A .25 ppm ammonia reading on a salicylate test kit under the common tank conditions and dechlor (or other needed additive) dosing where a fish in cycle is being done and exposure times are much more limited. The one thing that study does for sure is to indicate one should not keep baby fish in low levels of ammonia for extended periods (i.e. those exposure times significantly longer than during cycling).
 
The other interesting thing one can draw from the study is in regard to the .05 ppm level of NH3. While for the most part it was not significant, it was not completely so. And the descriptions from the above study would seem to be in agreement with the Merck Veterinary Manual's conclusion that harm happens at .05 ppm.
 
You stated "I'm still confused why you keep using the term irreversible?  I've stated several times that I do not believe we can ethically ignore temporary pain and damage that will heal but you have not acknowledged this."
 
It is simple, life is not perfect. All living things are subjected to adverse experiences. Lets use humans as an example. No parent wants their child to suffer, they would never want then to break a leg. based on that sentiment it would seem wise to keep one's children wrapped in padding and to forbid them from going anywhere they might possible break a bone. But the fact is that one can not live life this way. So many children with break a leg. It will hurt, it will take time to heal, But in the longer run it will not have any long term impact. Yes is will be painful and unpleasant, but not a material consideration for the overall quality of life over the entire lifetime of the child.
 
Well it is the same for fish as far as I am concerned. A harm/pain free life is an impossible dream. Every living thing is likely to experience pain and injury as a part of being alive. So the question becomes one of a tradeoff. To protect the child from ever breaking a leg requires the child be deprived of the the good things in life to prevent a transient bit of suffering that causes no permanent or long term harm. A bad trade if you ask me. What is really important is to protect the child from serious harm, damage or suffering. There is a big difference between an ouch that heals and has no long term impact on quality of life and something more traumatic and with permanent consequences.
 
In the absence of reasonable evidence that short term low level ammonia exposure causes pain, in the absence of evidence that it causes irreversible damage that impacts the overall quality of life for a fish, I am unprepared to trade a likely non harmful level of ammonia exposure for a short period of time for a potentially damaging lower level of exposure for a longer time that may actually do so.
 
I also refute your assertion that the science I offered was only concerned with what kills fish and not lesser issues. "I've brought this subject up because your guidelines were based on research that was unconcerned with minor physiological effects on fish." Then how do you explain that I listed studies for you to look at with titles like Acute toxicity and sublethal effects, Acute and chronic toxicity of ammonia, Metabolic consequences of chronic sublethal ammonia exposure ?
I think these all look at either lower levels or longer term exposures and effects as well is death.
 
And I am not in agreement with using a .01 ppm level of NH3-N as the concentration that is a danger over the short term or which causes harm or pain, especially when very young fish are not involved. That is a number you chose. For my part, I do not think it is even .02 ppm when the time frame is days. And I can not find science that suggests it is in terms of those species relevant to most newbie hobby tanks and especially for the fish being used during a fish in cycle.

 

[daizeUK]

"Lets revisit the assumption that any level of ammonia exposure that can show up on a test kit harms fish and the fact that you appear to be basing this conclusion on the Arizona Univ. site"... I've made no such conclusion or assertion and i'm getting tired of being mis-quoted.
 
I'm not sure why you felt it necessary to pick that report apart piece by piece.  The results I was particularly looking for were effects on the gills and long-term damage to internal organs, which are precisely the points where the results diverge from control.  We've already summarized and discussed this report and concluded that it did not constitute sufficient research due to the length of time before dissection and age of the subjects.  I've already stated that I wanted to look for further research with shorter time durations, preferably on more suitable fish.  Finally, I'm not aware that I have disagreed with the conclusion of the report anywhere.
 
I agree that some short term pain can be an acceptable trade-off in the better interests of a fish's long-term welfare.  Can you say for certain that any attempt to reduce suffering would definitely result in increased long-term damage?  If not then there is no reason not to investigate non-'irreversible' damage in addition to permanent effects.
 
Regarding your offered studies on sublethal effects of ammonia - I did look at them and most of them were short abstracts not covering the depth of information I was looking for.  The point I made was specifically in reference to your Ammonia Toxicity charts, which you presented again in post #21 ".......... There is little need to do anything unless your tank parameters put you into the small red areas on the chart."  This in particular is what I am challenging since those red areas are based on figures where half of salmonids in a study died.

 

[TwoTankAmin]

You are correct - you have never specifically said 0 ammonia tolerance. I inferred it from what you have posted in the thread. I was wrong in claiming you stated that and aplogize for doing so.
 
The red areas you keep referring were determined by the person who made up the charts. He also chose the yellow to indicate the level was approaching being red.
 

The tables below will allow you to determine the toxic ammonia levels in your tank. For tests done on salmonids, half the salmonids tested died with exposure to .03ppm NH3 ( 1 2 3 ). To my knowledge, we have no hard numbers for goldfish, but my fancy goldfish lived through around .03ppm for several weeks without adverse effects.

 
So the issue really is what what one believes regarding what is toxic and in what amount of time. Now let me clarify my position one more time.
 
- I am referring to exposure periods which may be as short as 5 days or as many as 20 and likely to be someplace in between. This presumes that the fishless cycler has not crammed the tank full of fish. Too many fish usually requires a better remedy than just water changes.
 
-The tank involved is being dosed with one of the typical products like Prime or Amquel which work on chlorine and chloramine, heavy metals and will also detoxify ammonia and perhaps nitrite and nitrate as well.
 
-API or similar salicylate ammonia test kits are being used to test for Total ammonia ions and the kit results give a reading of .25 ppm.
 
Now for the really important parts
 
-I believe based on what I have read and seen, that the amount of NH3 where it becomes a concern is somewhere between short of .05 ppm (the point at which the Merck Veterinary Manual states harm will happen) but not lower than .03 ppm. Nor would I rule out .04 depending on the other parameters etc. Note this is within a time frame of 5 - 20 days and not more.
 
I assume the tank pH is not over 8.4/5 and the temp at that pH is not over about 83F (28.3C). If they are that would modify things. But that is really not common, imo.
 
-I do not believe that any level of ammonia one can detect with hobby kits is safe for the longer term. In an established tank the ammonia is consumed as fast as it is produced.
 
-If during a fish in cycle the fish start to show behavioral symptoms of stress- are at the surface or showing any signs of having problems swimming always- do a water change whether you read 0.0, .25 or 5ppm of Ammonia.
 
-I assume the fish involved are not very young or among those that have above average susceptibility to ammonia. Different advice would be given in that case. Most newbies don't tend to have those sort of fish.
 
If you can come across research that would show my numbers are clearly wrong, I would welcome it would modify my thinking accordingly.
 
If I have made my position regarding ammonia toxicity during fishless clear enough for now, I would love to kick around nitrite with fish or even ammonia and nitrite and fishless cycling.

 

[TwoTankAmin]

In poking around looking for more ammonia studies, especually those relating to exposure caused damage and post exposure recovery, I ran across something interesting and somewhat related. It was a study that investigate this but not for ammonia exposure, but for copper exposure. Copper is pretty toxic for fw fish. perhaps moreso than total ammonia. It was only available as an abstract:
 
Gill Tissue Recovery after Copper Exposure and Blood Parameter Responses in the Tropical Fish Prochilodus scrofa

Changes in Prochilodus scrofa gill tissue and in blood responses were investigated after 96-h copper exposure and transference to clean water. Gill damage was characterized by epithelial lifting, cell swelling, pavement, chloride and mucous cell proliferation, and blood vessel anomalies. Restoration of gill structure was slow, with no tissue improvements in the first 2 days in clean water. From the 7th to the 15th day, the recovery of gill tissue began to become evident, with complete recovery occurring on the 45th day in clean water. Hematocrit, red blood cells, and hemoglobin concentration showed a significant increase after copper exposure, remaining high until the 7th day after transference to clean water. Plasma Na+ and Cl− concentration decreased significantly and K+ increased significantly after copper exposure and, on the 7th day in clean water, plasma ions showed no significant difference from those in control fish. Gill tissue restoration took longer than the recovery of blood parameters, possibly implying extra energy needs, which may be critical, depending on the fish's life cycle.

from http/www.sciencedirect.com/science/article/pii/S0147651302921640
 
What is important is that the effects of the copper exposure were reversed simply by the fish being in clean water. If the gill damage from copper was reversible I do not think it is a stretch to think they might also be when caused by ammonia exposure. I am continuing to search the literature for relevant studies hoping to find something about ammonia.

 

[TwoTankAmin]

Here is another interesting paper from 2006 I came across. You can read the entire paper (not just the abstract). It is titled: The variation of nitrifying bacterial population sizes in a sequencing batch reactor (SBR) treating low/mid/high concentrated wastewater
 
It deals with the different types of ammonia and nitrite oxidizers, which prefer what level of substrate (i.e. ammonia, nitrite etc,) how different levels of disolved oxygen affect things and how different levels of ammonia or nitrite work to select the dominant bacteria stains at work.
 
http/www.environmental-expert.com/Files%5C5306%5Carticles%5C12678%5C401.pdf

 

[daizeUK]

If the gill damage from copper was reversible I do not think it is a stretch to think they might also be when caused by ammonia exposure. I am continuing to search the literature for relevant studies hoping to find something about ammonia.

 
Have a look at this (if you haven't seen it already) 1999 Update of ambient water quality criteria for ammonia
I can't copy and paste but Appendix 5: Histopathological Effects refers to several experiments conducted on trout and salmonids which demonstrated reversal of tissue damage after a recovery period in clean water.  In particular, trout that were exposed for 7 months at 0.05 mg NH3-N/L then allowed to recover in clean water for 4 months showed reversal of gill damage (page 119-120).  There are other cited examples, but I can't see any of the original documents in full. 
 
This proves that some damage to tissue and gills from low-level ammonia exposure can definitely be healed.  I am getting a strong impression from this data that it is better to expose fish to lower concentrations of ammonia for longer periods, after which they will heal the temporary damage, than to expose them to higher concentrations which other studies have shown can cause irreparable long-term damage to liver and kidneys.
 
Something else caught my attention - Page 118 – the affects of ammonia on growth are not consistent with pH.  Higher concentrations of unionized NH3-N are needed to cause an appreciable affect on growth.  This is measuring in NH3-N so it is unrelated to the fact that there are higher concentrations of unionized NH3 at higher pH, which we already know.  But could this indicate that this effect of increased de-ionization is slightly counterbalanced by a decrease in unionized NH3 toxicity at higher pH?
 
I haven't yet had a chance to read your last paper on bacterial population sizes, so I will be back!

 

[TwoTankAmin]

Interesting paper. I would like to see more of the studies it quotes. While NH3-N is the more relevant ammonia reading, one con not totally ignore the NU4+ component. especially when exposure stretches beyond a few weeks anor/or involves young fish or eggs. Moreover, the paper is from 1999 and quotes lots of works even older. I would love to find some more recent studies which would confirm or refute some of the findings.
 
The most interesting take away related to the parts where it indicated the damage, in many cases, was not permanent. It would seem to imply I may actually be conservative in my thinking about what levels of ammonia during fishless cycling inflict what potential harm short term vs longer term. While many of the studies we have been looking at are able to point out short term negative effects while also indicating that growth rates are often not changed. What the studies do not investigate is the long term effects on lifespan. It is one thing to say that a fish grew normally it is another to be able to conclude that its lifespan was not shortened. I am not even sure one could design an experiment in this regard.
 
Given that we have clearly seen that different fish have differing tolerances to ammonia or nitrite and that they also have differing lifespans, can one even generalize between species if one were able to conduct lifespan related investigations. I have clown loaches that are with me for over 10 years and were several years old when I got them. I know a pleco breeder who has a male zebra pleco that is still spawning despite the fact it is over 20 years old. And we all know how long some of the carp can live. So how can we ever get a handle on how such long lived species are effected by ammonia or nitrite exposure at a much younger age?
 
What we should both find interesting about all this is we clearly are seeing lots of evidence that many of the things stated on sites as fact regarding cycling, the effects of ammonia and nitrite exposure, how the bacteria live, reproduce and can survive adverse conditions would seem to be out of step with the available science.

 

[TwoTankAmin]

I love it when I come across relevant information after-the-fact. here is an interesting abstract:
 
 

Swimming behavior as an indicator of sublethal toxicity in fish
 
Swimming behavior of fish is impaired by exposure to a diversity of contaminants. Gross aberrations in swimming can be qualitatively assessed while subtle changes in swimming behavior arising from sublethal exposures can be detected through a more detailed analysis of this response. Compared to other swimming behavior variables, the physical capacity to swim against water flow tends to be affected at relatively high toxicant concentrations and often presages mortality. Orientation to water flow, however, is altered at sublethal concentrations. Frequency of activity is a more sensitive measure in detecting contamination than measurements of survival alone. Alterations in swimming behavior have been detected during exposures to various contaminants at concentrations as low as 0.7 to 5% of their LC50 values and at concentrations that subsequently inhibited growth after longer periods of exposure. Analysis of swimming patterns provides even higher resolution for analysis of swimming behavior, and increased availability of the instrumentation necessary for such measurements should facilitate use of this approach. Fish swimming activity can easily be incorporated in test protocols to expand the sensitivity of standard toxicity tests.

http/onlinelibrary.wiley.com/doi/10.1002/etc.5620090103/abstract