Quote Originally Posted by Sir Patrick View Post
12-14 fish in a couple months is alot of fish, especially for a fairly new tank. Maybe you stocked too fast? Maybe your system couldnt handle the load yet? Also- could be many other things...

How old are your test kits, and what kind are ya running? No matter what, I would get a water test from an outside reliable source, just in case.
Awesome suggestions!

Hows your oxygenation in the tank? Are you getting good surface ripples and stuff? Temperature comes to mind, no heaters issues of anykind?