Originally Posted by ktreffin
I would have to agree with the presence of poor water conditions. What kind of fish were in the tank before you added the new? Could it be possible that they were harassed by the other established tank residents, which added stress contributing to the death?
Nitrates are the end result of the nitrogen cycle (ammonia to nitrite to nitrate) the only real way to control the amount of nitrate is through water changes. Seeing that the tank has been established for such a long period of time, and if water changes have been few and far inbetween, then a high nitrate level would be expected. I hope this helps. Good luck.
Actually, Ken, Thats not the only 'real' way to get rid of high nitrates. Putting some live plants in the tank really does help. They take in nitrate's so it helps lower the nitrate. If the nitrate's is the problem I would try that first, plus the water changes. If we could get some water spec's that would be great in helping you with the situation. Someone should make a sticky on here saying when you are posting a subject that you need help with always give the water stats, how big it is, what fish you have, has it been cycled ( depending on the problem, this would help ), and how long established. Hope this helps.