cold water fish dieing

Question
please could you give me a bit of advise on cold water fish.in a matter of days i have had five o my fish die for know reason.i keep the tank water clean,but they have died one by one.i have know idear what i,m doing wrong a part from that i did buy a new pump and followed the instructions to the pump closely.my fish were fine and healthy in the lasttwo months but now they have all died a part from the two that are left.
please help....

Answer
Hi Chris,
 Unfortunately that is really hard for me to say.   I assume from your message that you have an air pump providing oxygen into the tank and some sort of filter to keep the water clean.  Are you doing regular weekly water changes?  You need to be changing about 25% of the water once a week, every week, to keep your fish happy and healthy.

-- Ron C.
  rcoleman@cichlidresearch.com
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