Chicilid tank

Question
I have a 150 gal. african chicilid tank and all of my fish have been dying lately. I had a bacterial issure with my fish and I treated them and the surving ones have been fine with no symptoms. My water is a little green and I have been trying a couple of alage meds. (along with 25% water changes), but nothing seems to work. When I get my water tested everying is in normal range and everyone fish person I talk to at the pet stores around here say that my fish shouldn't be dying and that my water is testing safe?! So I put some new chiclids in and guess what they all died!!! It seems like their mouth gets stuck open and they swim around like crazy and then just dye. I have pleanty of airstones in the tank so I know they have enough O2. Any advice?

Answer
Hi Melissa,
  The green (algae) in the water is not a problem for the fish at all.  In fact, many fish eat the algae.  
  When you say "all" of your fish have been dying, is there one (large one) that has not?  Could it be that he is terrorizing the new ones?

  When you say "25% water changes", how often are you doing that?   You should be changing 25% of the water once a week, every week, to keep the tank happy and healthy.  

  I assume that you have a proper filter and heater on the tank -- do you? Also, what temperature is the water (it should be about 78oF or so).

-- Ron C.
  rcoleman@cichlidresearch.com
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