OP
OP
ZephyrStarPlaties
Fish Crazy
Yep!
Do I Need To Cycle This Tank?
- Thread starter ZephyrStarPlaties
- Start date
TwoTankAmin
Fish Connoisseur
Bignose- I know the evidence is anecdotal.
Aside from that statement a lot of what you posted is not scientifically factual. The bacteria you talk about- the higher level ammonia oxidizers are not what we want or need in our tanks and they do not last in there long term.
An established tank is a very low level ammonia environment which favors the bacteria identified by Dr. Hovanec et. al. and confirmed by others since. One of the most interesting things you can read in the published paper identifying the ammonia oxidizing bacteria in fw tanks is the fact that even when other ammonia oxidizing bacteria were in a tank at the start of cycling, when the cycle was complete, only one strain remained.
/www.drtimsaqu...c-AEM_Dec01.pdf
The ammonia level selects for the strain in the long run. And this study of a sw aquaculture system confirms this sort of selection process.
/www.ncbi.nlm....pubmed/18093145
(Interesting that in both fw and sw Nitrosomonas marina like bacteria were about 2% of the total bacterial population.)
There are many other studies about the fact that ammonia levels determine which AOB are favored in a given environment. In a fish tank there should be mostly the lower level ammonia lovers. And that is why I keep arguing in favor of dosing lower ammonia amounts to do a fishless cycle. 2 - 4 ppm should be sufficient at the start (5ppm is the absolute max.). Daily dosing is not needed, and future doses should be between 1/4 and 1/2 the initial amount. This method is simple, effective and relatively fast. It goes even faster when you seed. It also avoids and chance at encouraging the bacteria we don't really want.
The idea that a 5 ppm limit is suggested by anything other than lab studies which show that at over 5 ppm levels of either ammonia or nitrite, there is an inhibitory effect on the desired nitrifying bacteria which can start to become fatal as well if it goes higher. Nor does this information come solely from tank related studies. To find a lot of them go to Google Scholar then select for Articles excluding patents and to make life simple choose since 2000 as the time frame and then enter "AOB + ammonia inhibition" (AOB= ammonia oxidizin bacteria) after sorting through the 1470 odd responses, go back and change AOB to NOB which will run it for nitrite oxidizers and scan the 1260 odd results. The point is with all the potential for new fishkeepers to accidentally cross the 5 ppm line, it seems more sensible to guide them short of it.
As for the idea that bacteria which normally live in moist or wet environments can not survive a drying out ot that environemnt. Again the science says differently. The nitrifyers in our tank live in other places, most notably in the soil. Now the soil is not aquatic, but it is normally moist. So lets ask ourselves how the following is possible if the bacteria can not survive drying out.
/www.sciencedi...038071707004683
The point is some number seem to be able to survive dry environs for a very long time. No it isn't most, nor perhaps a lot, Bu the fact that some do means they can. And I do not think it is a stretch to say the shorter the time, the higher the odds that many or even most would survive. 30 days in a dry sponge is way less than decades in dry soil.
The bacteria in our tank, once established, live in a bio-film they produce. There are all sorts of other bacteria cohabiting and also contributing to the bio film. This film can retain moisture for some time. As you will note in my original post, I said there are variables which would effect how many bacteria might survive and for how long etc. etc. What appears dry to you or me inside a filter sponge is not the same thing to a bacterium. To be able to get a good look at one requires and electron microscope to give you an image which has been magnified 39,000 times. The OP seems to have managed to have viable bacteria survive for 30 days, not years or decades. As long as it did not get to hot or cold (i.e freezing) some bacteria can and do remain viable and culturable for some time even in a seemingly dry environment. The go dormant in their bio-film and await better times.
Finally, I would like to look a little more closely at your assertion that a typical aquarium produces 1-2 pm of ammonia a day. I do not know if this is correct or not. But I will assume, for the moment, that it is true. Now we know this level of ammonia doesn't all appear in one instant, rather it is produced all day long. To simplify things lets assume the ammonia is generated at a level rate all day long. So to produce 1 ppm in 24 hours we can say 1/24 ppm is produced an hour. That is .0416 ppm an hour. And if we look at a daily total output of 2 ppm, it is still only .0833ppm/hour. So exactly how much bacteria does it take to process that kind of ammonia level?
2 ppm daily output times 3 = 6 ppm., and yes it will stall the cycle. I have posted all of this before on this site. It has to do the the lag factor in establishing the nitrite oxidizers which everyone agrees takes longer that the ammonia oxidizers to reproduce. You dose ammonia to encourage the growth of the AOB, as they multiply they put out nitrite. And as long as there is ammonia going in, there will nitrite coming out. But the reproductive time difference adds a 2nd layer. Think of it as a race. Because we only dose ammonia, its like giving the AOB a head start. They are off and multiplying and creating nitrite before the NOB can even start eating and multiplying. But once they are allowed to start, because they reproduce slower its like they are running slower than the AOB. The danger becomes the nitrites go over 5 ppm and that is the real killer.
As I have posted in other threads, the science would indicate that it may not be the nitrite per se that does the damage but a by product in the form of nitrous acid (six of one, half dozen of another). The point is that dosing too much ammonia may actually cause nitrites to be the killer by making too many of them. The easiest way to avoid this, as well as to avoid too high and ammonia reading is not to dose ammonia above 5 for sure and dosing levels between 2 and 4 ppm are even safer/better.
Fishless cycling has come a long way since it was first proposed in 1999. Back then Dr. Cow used the drops per 10 gallon method which is what I used. He revised this to the dose and test method in 2004. While I understood the reasoning behind this change, I preferred to stick with the drops/10 gal method. I have not seen any further revisions from him since, However, Dr. Cow is a biochemist and I think the work done by microbiologists has provided the final, or at least most recent, chapter. The result is that the amount of ammonia involved has gone down since Dr. Cow's work.
Over that time almost everything I believed about cycling and the bacteria turned out to be wrong. It only took me close to 10 years and reading a ton of scientific stuff that was no fun, to learn that.
Aside from that statement a lot of what you posted is not scientifically factual. The bacteria you talk about- the higher level ammonia oxidizers are not what we want or need in our tanks and they do not last in there long term.
An established tank is a very low level ammonia environment which favors the bacteria identified by Dr. Hovanec et. al. and confirmed by others since. One of the most interesting things you can read in the published paper identifying the ammonia oxidizing bacteria in fw tanks is the fact that even when other ammonia oxidizing bacteria were in a tank at the start of cycling, when the cycle was complete, only one strain remained.
From http
/www.drtimsaqu...c-AEM_Dec01.pdf The ammonia level selects for the strain in the long run. And this study of a sw aquaculture system confirms this sort of selection process.
From http
/www.ncbi.nlm....pubmed/18093145 (Interesting that in both fw and sw Nitrosomonas marina like bacteria were about 2% of the total bacterial population.)
There are many other studies about the fact that ammonia levels determine which AOB are favored in a given environment. In a fish tank there should be mostly the lower level ammonia lovers. And that is why I keep arguing in favor of dosing lower ammonia amounts to do a fishless cycle. 2 - 4 ppm should be sufficient at the start (5ppm is the absolute max.). Daily dosing is not needed, and future doses should be between 1/4 and 1/2 the initial amount. This method is simple, effective and relatively fast. It goes even faster when you seed. It also avoids and chance at encouraging the bacteria we don't really want.
The idea that a 5 ppm limit is suggested by anything other than lab studies which show that at over 5 ppm levels of either ammonia or nitrite, there is an inhibitory effect on the desired nitrifying bacteria which can start to become fatal as well if it goes higher. Nor does this information come solely from tank related studies. To find a lot of them go to Google Scholar then select for Articles excluding patents and to make life simple choose since 2000 as the time frame and then enter "AOB + ammonia inhibition" (AOB= ammonia oxidizin bacteria) after sorting through the 1470 odd responses, go back and change AOB to NOB which will run it for nitrite oxidizers and scan the 1260 odd results. The point is with all the potential for new fishkeepers to accidentally cross the 5 ppm line, it seems more sensible to guide them short of it.
As for the idea that bacteria which normally live in moist or wet environments can not survive a drying out ot that environemnt. Again the science says differently. The nitrifyers in our tank live in other places, most notably in the soil. Now the soil is not aquatic, but it is normally moist. So lets ask ourselves how the following is possible if the bacteria can not survive drying out.
from http
/www.sciencedi...038071707004683The point is some number seem to be able to survive dry environs for a very long time. No it isn't most, nor perhaps a lot, Bu the fact that some do means they can. And I do not think it is a stretch to say the shorter the time, the higher the odds that many or even most would survive. 30 days in a dry sponge is way less than decades in dry soil.
The bacteria in our tank, once established, live in a bio-film they produce. There are all sorts of other bacteria cohabiting and also contributing to the bio film. This film can retain moisture for some time. As you will note in my original post, I said there are variables which would effect how many bacteria might survive and for how long etc. etc. What appears dry to you or me inside a filter sponge is not the same thing to a bacterium. To be able to get a good look at one requires and electron microscope to give you an image which has been magnified 39,000 times. The OP seems to have managed to have viable bacteria survive for 30 days, not years or decades. As long as it did not get to hot or cold (i.e freezing) some bacteria can and do remain viable and culturable for some time even in a seemingly dry environment. The go dormant in their bio-film and await better times.
Finally, I would like to look a little more closely at your assertion that a typical aquarium produces 1-2 pm of ammonia a day. I do not know if this is correct or not. But I will assume, for the moment, that it is true. Now we know this level of ammonia doesn't all appear in one instant, rather it is produced all day long. To simplify things lets assume the ammonia is generated at a level rate all day long. So to produce 1 ppm in 24 hours we can say 1/24 ppm is produced an hour. That is .0416 ppm an hour. And if we look at a daily total output of 2 ppm, it is still only .0833ppm/hour. So exactly how much bacteria does it take to process that kind of ammonia level?
2 ppm daily output times 3 = 6 ppm., and yes it will stall the cycle. I have posted all of this before on this site. It has to do the the lag factor in establishing the nitrite oxidizers which everyone agrees takes longer that the ammonia oxidizers to reproduce. You dose ammonia to encourage the growth of the AOB, as they multiply they put out nitrite. And as long as there is ammonia going in, there will nitrite coming out. But the reproductive time difference adds a 2nd layer. Think of it as a race. Because we only dose ammonia, its like giving the AOB a head start. They are off and multiplying and creating nitrite before the NOB can even start eating and multiplying. But once they are allowed to start, because they reproduce slower its like they are running slower than the AOB. The danger becomes the nitrites go over 5 ppm and that is the real killer.
As I have posted in other threads, the science would indicate that it may not be the nitrite per se that does the damage but a by product in the form of nitrous acid (six of one, half dozen of another). The point is that dosing too much ammonia may actually cause nitrites to be the killer by making too many of them. The easiest way to avoid this, as well as to avoid too high and ammonia reading is not to dose ammonia above 5 for sure and dosing levels between 2 and 4 ppm are even safer/better.
Fishless cycling has come a long way since it was first proposed in 1999. Back then Dr. Cow used the drops per 10 gallon method which is what I used. He revised this to the dose and test method in 2004. While I understood the reasoning behind this change, I preferred to stick with the drops/10 gal method. I have not seen any further revisions from him since, However, Dr. Cow is a biochemist and I think the work done by microbiologists has provided the final, or at least most recent, chapter. The result is that the amount of ammonia involved has gone down since Dr. Cow's work.
Over that time almost everything I believed about cycling and the bacteria turned out to be wrong. It only took me close to 10 years and reading a ton of scientific stuff that was no fun, to learn that.
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