I don't know why this is happening but my nitrites are going up and right before I am goig out of town. The tank has been cycled for over 2 years and 3 days ago when I checked the params (using API drops) things looked as they usually do with ph: 7.6-7.8, amm:0-0.25, nitrite:0, nitrate: 10. Today when I checked the nitrite was up to 0.25-0.5 but the ammonia was still 0-0.25 and nitrate 10-20 (I checked 3 times to be sure). Why would nitrites go up with the others staying constant? I checked my other tank and the nitrate was ok so I think the test is accurate. The only thing I can think of is that I recently started giving peas for the first time since my fish have constipation/SBD problems. Also I had used marcyn2 but finished this up over 2 weeks ago with no change in params noted until now.

I just did a 25% water change using extra Prime and will do another one in a couple of hours. The other problem I have is that the tap pH is very high ~8.5 and the tank pH is 7.4-7.6 so I am afraid to do too big a water change at one time.

I would appreciate any ideas/suggestions for what caused this/what to do as I am leaving town tomorrow and need to get this straightened out.

Thanks, sea

have you recently cleaned the filtration system? Maybe you cleaned it too well and caused a bump in your cycle?

I don't honestly know I have an eclipse with a biowheel and was under the assumption that most/all the bacteria was in there? I did not do anything to the biowheel but did rinse off the filter cartridge in tank water on Sunday (usually do this once a week or so).

That brings up a question I always think about but don't really know the answer to - can your tank/water be too clean? I usually do two 25% water changes and vacuums /week and my params hold at amm:0-0.25, nitrite:0, nitrate: 5-20. Is it possible that if the nitrate level fell too low that this could effect the cycle? I don't understand how this could be so if the bacteria are in the biowheel and not the water though. If this is the case should I do more water changes now to get the nitrites down or not? It figures that this has to happen now that I am going away and can't monitor things

--sea

Test your tap water, it may have changed.


Also, ammonia should never be .25 in a cycled tank. Maybe your drops are off.

I don't think low nitrates would throw off your cycle. Actually, I'd say keeping your nitrates in the 5-20 range is great!

Which Eclipse system do you have? How big is your tank and how many fish? Perhaps they are getting too big and the filtration is not able to keep up anymore?

Well I am just back from vacation and happily my fish are fine and surprisingly my water is fine too. I can't really understand what happened to mkae the nitrites go up like that. I did a 25% change using a double dose of Prime before I left and fasted my fish (and worried the whole time) and now that I am back the ammonia is still 0-0.25, the nitrites are back to 0 and the nitrates are up to 20. Weird!

You may be right though about the filtration. I have 2 fantails (~1-5-2 in ea) in a 12 gal eclipse (been running for 2+ years). I am very carefull to change water, vacuum gravel and monitor params since I know I am overstocked. However, I had been feeding the fish a lot more than usual since they were on medigold for a bacterial infection and I wanted to get in as much food as possible. Then they became constipated and I added peas as well. Maybe I just overdid it on the food and this was too much for the filtration?

Anyway thanks for your help!

--sea

EDid you say that you checked the nitrites 3 times to be sure? A few weeks ago I thought my nitrites had suddenly gone up, I was totally freaking out but when I retested a few minutes later everything was fine! Maybe I added too many drops or something. But I think you said you checked more than once.

I am glad your fish are fine!