lost 50 fish in 48 hrs

Question
Hi,

I have had a tank for about 2 weeks and everything looked ok. No sign of any diseases. All of sudden fish started dying 10- 15 everyday. Can not realy understand why? aeration is good and filter is pretty good as well.
Anything that I should check?

Answer
Hi Afshin,
  I am trying to understand your setup.  You have a new tank with 50 fish in it?   That is WAY too many.  You need to start a tank with a few fish and gradually add fish.  Putting that many fish in a tank at once will cause an incredible "bounce" in the ammonia level in the tank which could easily kill all the fish.  

-- Ron
  rcoleman@cichlidresearch.com
  Cichlid Research Home Page <http://cichlidresearch.com>