my 6 yr old oscar is very sick

Question
My oscar has had popeye and hole in the head for over 6 months now. We have treated him 4 times and nothing has worked. it started when we put a pleco in the tank with him about a yr ago. and after a few wks the pleco died so i think it infected my oscar. his right eye is really popped out and the other has white over it. he's totally blind now and i don't know if he is suffering. he eats normally, but i dont know if he is in pain. when do i let go of my very much loved oscar and how do i know when to youthanize a fish and how?

Answer
Hi Nora,
 Have you been doing regular weekly partial water changes?  You should be changing 25% of his water once a week, every week to keep him healthy.   If you start doing that immediately, his health might improve substantially.

-- Ron
  rcoleman@cichlidresearch.com
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