Mid Cycle Question

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RobRocksFishTank

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About 9 days since 2nd feeding at 80 deg F.
 
Ammo - .25 ppm
Trites - 5.0+
Trates - ~20
 
This is a 120 gal. freshwater community tank and will be stocked lightly to start and slowly populated from there. Planning on some live plants.
 
Can I do a water change (hoping to speed up cycle) or just let it ride?
 
A water changes slow a cycle that isn't stalled.
 
One should plant first. Plants need to settle in before one adds fish or else the plants may become floaters. Given sufficient plants and a slow addition of fish there is no need to cycle at all.
 
There are two primary benefits for doing a fishless cycle, the first is no fish can be harmed. The second is it allows one to fully stock their tank right away. Slow stocked basically indoes the point of fishless for the most part.
 
Fisless cycles are done using an ammonia level that insures any tank will be safe for fish, This includes rift lake tanks which are frequently overstocked to blunt agression and uin which any ammonia is much more toxic due to the higher pH levels in such tanks. It also has a fail safe level built in. It is better to have to much bacteria than too little when one add that full load.
 
If one is cycling a tank with only a few plants which wont be usfficient to protect the tamk, it is still important to plant first and wait 10-14 days and then commence a cycle but at a 2 ppm level rather than 3.
 
Plants use ammonium and nitrate. So when one needs to do some cycling, how much is mitigated by how much ammonia the plants might use. The result is that one will see ammonia disappear faster, may see less or no nitrite and the same for nitrate.
 
The problem is there are many plants. many possible mixes and levels of planting. This makes it impossible for inexperience plant people to know how much, if any bacteria, they may need to cultivate nor the best way to do it. Finally, some plants can be harmed by the ammonia levels used to cycle.
 
What I suggest to folks is they plant the tank, let it settle in and then if they are not sure, they can use one or two test ammonia doses to figure out what is up. If worried about potential ammonia damage, start by adding 1 ppm and testing in 24 hours. If the results are 0/0, you can try again with 2 ppm. If this is also 0/0 in 24, you don't really need to do any level of cycling. And don't forget that plants arrive with bacteria on them, so when you plant a tank you are also adding some amount of bacteria as well.
 
I love Zebra Plecos! (Just had to get that out there for TwoTank's avi.)
 
I was hoping for a yes or no answer with maybe a short explanation. I'm sorry you may have wasted your time with all that info as it does not apply to me. (Hopefully, someone else can use it.)
 
Correct me if I'm wrong. High Nitrites can inhibit the growth of the bacteria that eat it. At 5.0 ppm I'm off the chart. They have been there for at least 9 days. I did not test for them until the Ammo went down. Since my Nitrates have gotten close to a level (for an established tank) that would indicate it was time for a water change, I'm pretty sure I've got enough of those bacteria to continue the cycle. Especially, since I plan on stocking slowly. I don't need to grow the colony any further but the food is already there so that is going to happen. I'm thinking that if I bring the levels down, the colony will process what's left.
 
FYI, when I started the cycle, my plan was to do a Tanganyikan biotype tank. I changed my mind because I wanted to be able to use my water changes for watering my garden. The plants were also an afterthought.
 
So, what would you suggest I do given the above parameters? I plan on starting with a bunch of small fish and a few small plants. (I like to watch things grow.) The fishless cycle thing was new to me but I've cycled countless tanks and quite a few multi-tank systems with fish quite successfully.
 
Do I let it ride or try a substantial water change to lower the levels hoping that the Nitrites drop down to zero quicker?
 
You are  correct. But the level on an API kit to stay under is 16 ppm. Oops the kit stops at 5. If one is using the fishless cycling instructions here and following them to the letter, it should be impossible to get that high. If you really want to know what level they are at, see this article for how to do diluted testing http://www.fishforums.net/index.php?/topic/433778-rescuing-a-fish-in-cycle-gone-wild-part-il/
 
Because you have only tested once and we cannot determine the actual level, we have no clue how nitrite has been moving. Most newer hobbyists will injure and/or kill fish trying to do a fish in cycle. If you are certain you are in control with one, then just do a water change and get the numbers down to 0/0 and then plant and do a fish in. You will have a decent jump start on the ammonia bacs and you can deal with any nitrite by adding salt. Also explained how in that same link.
 
In a fishless cycle high nitrate can stall a cycle by causing the pH to drop towards 6.0. That is one of the times one must change water to correct the situation.
 
What I suggest you do if you want to finish the cycle before you add plants/fish is based on my understanding of what you have stated so far. I am thinking, based on your description, that you have been cycling for about 20 days or so. If this is correct in about 3 days or so add a 1/3 dose of ammonia and then follow the directions in the cycling article here article here. I would make one change to it based on your stated plan. When you get to the final ammonia addition or two, lower the amount to 2 ppm instead of 3 ppm for these. When you add the plants you will also be adding some more bacteria to the tank.
 
Thank you. That helped.
 
To sum it up. Water change and then add low ammonia dose. If Ammonia and Nitrite are 0 within a day, good to go.
 
No, a bit more than that.
 
1. In about 3 days add a 1/3 snack dose of ammonia. Test regularly.
2. Now, whenever you test and ammonia is .25 ppm or lower and nitrite is clearly under 1 ppm it is time to add another 2 ppm of ammonia and then test in 24 hours.
3. If ammonia and nitrite both read 0 ppm, you are cycled. Do a large water change, be sure the water is the proper temperature, and proceed. The odds are this will not be the case quite this soon. But it may be.
4.  If ammonia and nitrite do not both read zero, continue to test daily. Whenever ammonia is again at .25 ppm or less and nitrite is clearly under 1 ppm, add 2 ppm of ammonia and test in 24 hours. Follow this pattern of testing and adding  until both tests do read 0 ppm within 24 hours. The cycle should not take much longer to be completed and even with slower tanks one should not need to go beyond two or three such additions.
 
All your additions beside the snack should be at 2 ppm. Your other option is the big wc and a return to fish in as I wrote above.
 
I didn't remember your directions quite right. I did the water change on the 11th and added the snack the same day.
 
Ammonia went down to .25 ppm the next day.
 
Nitrites were and are still off the chart.
 
Did dilution tests:
2:1 - off the chart
4:1 - off the chart
 
I have to admit, I think I'm having trouble reading the chart, but I can see a difference between the 2:1 and the 4:1.
 
Tested tap water. It is zero.
 
Is a careful, near 100% water change still on the table or should I let the cycle ride out?
 
I would do the water change this weekend and get fish and plants during the week if everything stayed zeroed out.
 
Thanks for all your help. Your directions for fishless cycling posted under the Cycling tab are well written.
 
I have to admit that I did not read the article about diluted testing, I just winged it. Hope it made sense.
 
If you are convinced that your nitrite is over 16 ppm after a diluted test- then you do need to do a water change. You do not have to get anywhere near all the nitrite out.Iif you reduce it towards 10 ppm on the API diluted test, you are fine.
 
However, bear this in mind. The most nitrite that 1 ppm of ammonia can possibly make is 2.55 ppm. If all you did was to add 3 ppm twice and then 1 ppm your total is 7 ppm. That means your nitrite should not be above 7 x 2.55 = 17.85 ppm. However, for the nitrite to get to the max level is not likely since, as soon as nitrite shows up from the first ammonia dose, the nitrite bacs start to multiply and continue doing so unless your nitrite gets too high. So they will have processed some of that nitrite along the way. For partial conversion in the case of adding a total 7 ppm of ammonia it only needs about 3 ppm of that potential total to be reduced to nitrate to get the reading under 16 ppm.
 
So if you did the dosing according to how it is laid out in the article, it is almost impossible to get nitrite at cycle stalling levels. The entire dosing regimen in that article is designed to make it impossible to get nitrite too high as long as the directions are followed to the letter. And, in your case doing a water change, which is not suggested unless things go wrong, would have worked to remove ammonia and nitrite as a side effect. So, if you have indeed only dosed 7 ppm of ammonia and then you have done a water change, your test readings cannot be correct. If you changed just 20% of the water with nitrite at 17.85, the result would have been a reading of nitrite at 14.28 ppm. And if you changed more, then that number should have been even lower.
 
At a 50% dilution a 5 ppm nitrite reading indicates a level of 10 ppm or more, at 75% dilution it means 20 ppm or more. Note, I did not use the terms 2-1 or 4-1 but rather the %s of each water source.  2:1 or 4:1 are ratios, they would imply 2/3 and 1/3 or 4/5 and 1/5. At 75% dilution 1/4 of the reading is real since 1/4 of the water is from the tank. That is why the factor is to multiply by 4. In the normal test, without dilution, the factor would be 1 x the result. Doing the math in reverse makes this clearer. If you had 20 ppm. 1/4 of this is 5 ppm. The danger of using the 2:1 or 4:1 designation is, if used, it does not mean the same thing.
 
For those out there who are nudges about this sort of thing- the 50% test has a 1:1 ratio of tank to distilled while the 75% dilution has a ratio of 3:1.
 
Unfortunately, I used a different article to start my cycle. It said don't worry if you overdose the first time, which is exactly what I did. I wasn't doing the test properly and way overdosed. I did do a major water change as soon as I realized my mistake but I'm pretty sure the result was still over 5 ppm.
 
Is there any reason why I shouldn't do a 100% water change?
 
I'm thinking, do the change and add another snack dosage. If ammo and nites are 0 within a couple days, I'm good to go on some inexpensive fish and plants to test the waters.
 
Since my last post, I did a close to proper diluted Nitrite test. Again, I used tap water but got the percentages correct. 25% looked like it was off the chart or at least at the high end. (I think the color chart is off enough for me to not really read it properly.) I went ahead and did the 12.5% test and that looked like it was about 1 or 2 ppm. Tested Nitrates - about 20 ppm.
 
Went ahead with major water change to lower 'trites, since ammo is getting processed quickly.
 
How long should I wait to do snack feeding? Or should I just get fish?
 
I am planning on stocking very slowly with small fish and some plants.
 
I find it hard to help folks pull off cycling using a method of which I do not approve, it usually creates problems. Using tap is not the way to do diluted testing.
 
But before I can help I would have wanted to know the ammonia reading after the water change.
 
Seeding changes all the numbers one will get from the very outset. So it is difficult to use the article as written. The reasons are:
 
1. Ammonia is processed sooner and faster.
2. Nitrite levels never hit the numbers listed.
3. Nitrate numbers will appear much sooner and move up faster.
4. The timing and the expected readings will not work according to the article.
 
Basically the biggest change will be to the nitrite numbers. This is because one starts with a lot more of the nitrite bacs than normal. So instead of nitrite shooting up while the bacteria multiply to handle it, the bacteria present handle a bunch of it right away. Then, since one has started with more of them, the reproduction process is jump started and takes less time. The more bacteria we can start with, the less that must be grown for a tank to be cycled.
 
One needs to be a bit more familiar with the cycling process when using seed bacteria because you have to more or less feel and test your way to know what is up.
 
if you do not want to mess around testing etc. Do as big a water as you can. Refill and dechlor. If you are using Prime or other ammonia detoxifying dechlors, they will distort test result in short order, so you can not test ammonia reliably for at least a day. After you have refilled the tank and dechlored, test right away. You are looking for any ammonia or nitrite, ignore nitrate. You should have 0 ammonia, which we want, but record what you do have, if any. Then test for nitrite and record that too. Next, use the ammonia calc, remember to reduce the volume for decor etc. as the cycling article states. Then add the amount of ammonia needed to produce 3 ppm in your volume of water. (If you did test any ammonia before you prepare to add the new dose, make the new dose smaller by whatever amount of ammonia you showed in the test. i.e. if you test .25 ppm the new dose would be 2.75 ppm to make a total of 3 in the tank.)
 
Wait at least 24 hours and test. Unless both ammonia read 0/0, you are not cycled. If you are not cycled wait for ammonia to hit 0 and nitrite to be .5 or less and dose to 3 ppm again and follow the same process. With seeding, the snack dose should usually not be needed.
 
I understand that it is difficult to advise me since I messed things up on day one. I do appreciate all the advice you have given me. I've taken what you have said and tried to apply it to my situation. I'm hoping levels get to zero tomorrow so I don't have to mess around any more. If I do, I will keep the reins a bit tighter.
 
Thank you very much for writing such detailed responses.
 
Update:
 
I messed up again. 24 hours after water change I added ammonia but forgot to test before adding it.
 
I only added a 1/3 dose hoping that if levels were 0 after 24 hrs, I would be good to go with a batch of hearty fish.
 
Again, "this is a 120 gal. freshwater community tank and will be stocked [very] lightly to start and slowly populated from there. Planning on some live plants."
 
I figured the 1/3 dose would more than cover the bioload for the initial stocking. 
 
Ammo hit 0 today. Nitrites are declining. The colors on the chart (API) don't really correspond with the test results, but I'm starting to get a "feel" for it after seeing different results. I will definitely be able to tell when it's 0, though.
 
Once 'trites are down to 0, I think I should be good to go for a dozen White Clouds or Zebra Danios to "test the waters".
 
Objections?
Tips?
 
Thanks again to TwoTankAmin for all the info you posted. I hope someone else comes to this thread and finds it just a portion of how helpful it has been for me, even though I'm not following your advice to a "T",
 
I got off to a rough start before I found your articles and am trying to minimize the impact of my mistakes. They really nail down the numbers which other articles I read, kinda failed on.
 
You will find the Nitrates climb pretty fast if you have cycled well and @ 120gallons good luck with stocking containers to get rid of nearly 60% of water just to get rid of the Nitrate at a safe level, unless you have some chemical media to deal with it!
If you go down the route of fish in just remember high Nitrates are just as bad as the rest, but there is no bacteria to remove the Nitrate its all chemcial at that point. Unless you have a decent planted tank to soak up some of the Nitrate.
Soon as the tank has cycled stick some plants fella in there mate it will defo help with any chemcial spikes from stocking aswell.
 
It is not quite correct to say there are no bacteria for nitrate when there most certainly are. Every established tank has some number of denitrifiers at work. However, due to how most of us set up our filtration and then haow we do it will not normally promote sufficient numbers to handle all the nitrate which will build up over time.
 
To encourage denitrification requires one of several potential solutions. Well planted tanks with good root systems works well. they combine denitrifying bacteria in the substrate with the ability of plants to uptake nitrate itself. Another method is to use special media designed to encourage to colonization of the denitrifying bacteria deep inside the media. Finally, ine can set up a filter especially for encouraging denitrifyers to colonize and creating the conditions they need to thrive. This requires the use of both specifically designed media combined with a much slower flow rate than we typically use in our filters.
 
In essence, the denitrification is handled by bacteria which normally use oxygen. However, deeper in the biofilm where these bacteria tend to live there can be anaerobic areas created because the other bacteria have used up all the free oxygen before the water reaches these bacteria on its way through the media. When this happens what does reach them is the nitrate created by the bacteria which have used oxygen to turn ammonia into nitrate. But nitrate contains bound oxygen- it is 3/4 of nitrate which is NO3. Those 3 bound oxygens are used by the bacteria and what is left of the NO3 is basically N, usually as a harmless gas which leaves the water for the atmosphere. The bacteria that can make this switch are call facultative aerobes. So the nitrate is broken down because the free oxygen was made unavailable due to all the other microorganisms using it up within the media before the water reached the facultative aerobic bacteria which will then use nitrate instead.
 
And no, this does not mean all of the available oxygen has been stripped from the water and ones fish will be left gasping. This is all happening in very limited and specific areas. Plenty of well oxygenated water is flowing around a tank and media in a filter. In addition, the agitation of the surface is constantly replacing the oxygen. However, if there is neither free oxygen nor the bound oxygen in nitrate available, these same bacteria will turn to using sulfates and thenthey produces hydrogen sulfide. We recognize this as the "'rotten egg" gas and it is something we would prefer not to have in our substrate/water.
 
Finally, light stocking and going slowly combined with live plants will almost always remove the need to cycle a tank in the traditional fashion.  The more plants and the more patience one has for stocking, the easier this is. Normally, all I suggest in such cases is that one lets the plants settle in for a couple of weeks before one begins stocking gradually. Don't forget that plants arrive with nitrifying bacteria on them.
 

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