Nitrite issue... I can't believe it

[DGabbs]

In 12 years of cycling FW tanks I have never had this issue.

I fully completed my cycle, confirmed cycle was complete by adding ammonia and then testing for nitrites and ammonia. They were both 0 after a day or so.

A couple days later i added two figure 8 puffers, still very small and i have been feeding them conservatively and cleaning up extra food and poop afterwards.

Now my ammonia level is 0 (or close to) nitrates are low, but nitrites are at around 1ppm! I can't figure it out.

I have never cycled a brackish tank, but i have never even seen nitrites after any of my FW cycles. I think the pH is about 8.4, but those drop test kits can be hard to read sometimes.

Anyone know what could have happened? Throughout the cycle, nitrites were definitely the slowest moving process, but the cycle did complete.

Thanks

[bertie 83]

It seems like you may not have added enough ammonia to represent 2 puffers, daily 50% waterchanges using prime until this straightens out

[DGabbs]

It went down to .25ppm today which is encouraging, but still not zero... I'll do a 50 tonight and see where that gets me.

I put enough ammonia in the tank to maintain around 5ppm for the first few days. Thats usually enough for any fish that i have ever had, but then again these are puffers.

I thought that maybe i killed off that set of bacteria in a water change or something by swinging the SG, but it never moved any more than 0.002

Thanks bertie

[bertie 83]

Yea keep up the water changes and you will soon be there, probably just missed some minor detail which is just too easy to do. Good luck

[RTR]

If your ammonia dosing was at all over 5 ppm, that could damage the nitrite eaters. 3 ppm is plenty for cycling, higher ammonia titers can damage the bacteria required for nitrite oxidation.

That is a common error. Folks think that if a little is good, more must be better. It is not - it depresses the nitrite oxidizers and above 8 ppm can and will kill them. 10 ppm ammonia can and will eradicate the nitrite oxidizers totally. Excess ammonia is the commonest cause of extended cycle time.

If the ammonia phase of cycling is over 10 days to two weeks, you should re-inoculate the filter with bacteria to get healthy nitrite-oxidizers into the system.

[DGabbs]

If your ammonia dosing was at all over 5 ppm, that could damage the nitrite eaters. 3 ppm is plenty for cycling, higher ammonia titers can damage the bacteria required for nitrite oxidation.

That is a common error. Folks think that if a little is good, more must be better. It is not - it depresses the nitrite oxidizers and above 8 ppm can and will kill them. 10 ppm ammonia can and will eradicate the nitrite oxidizers totally. Excess ammonia is the commonest cause of extended cycle time.

If the ammonia phase of cycling is over 10 days to two weeks, you should re-inoculate the filter with bacteria to get healthy nitrite-oxidizers into the system.

Ya, maybe it was a little over 4-5ppm. You'd never know because it goes right from 4pmm to 8ppm on the test drop kit, and I know it wasn't 8ppm.

Good news though, I did a 30% water change yesterday night, and tonight I'm getting 0 ammonia, 0 nitrite, and less than 5ppm nitrate!

Thanks guys!

[J-P]

That is a common error. Folks think that if a little is good, more must be better. It is not - it depresses the nitrite oxidizers and above 8 ppm can and will kill them. 10 ppm ammonia can and will eradicate the nitrite oxidizers totally. Excess ammonia is the commonest cause of extended cycle time.

I wish I knew that when I set up my 500 gal took forever... Thank you for that extra little tid-bit

[RTR]

There is, or was, a note by me in the Library about it. We'll get it back if it not currently saved here. We did find a couple of oops! when we were popularizing fishless cycling via ammonia. The worse was that low KH water requires monitoring or it can crash. None of the group beta-testing had low KH water. Big OOPS! Next was that high-dose ammonia damages or kills the nitrite-oxidizers. That was funny because copycats jumped on the concept and wrote new article suggestion 10ppm ammonia, which will kill of the nitrite oxidizers before they get any nitrite to oxidize. We did enjoy those articles... Meow!

[Pufferpunk]

You only dose ammonia at 5ppm until you start seeing nitrite. Then you cut the dosing in 1/2.