oscar has poofy eyes

Question
hi my name is kassidy, me and my dad have a oscar,an opaco,and another fish i forget what its called,but my oscar has developed huge eyes that he didnt have last weekend they look like marbles and they are a light creamy colored and his eyes with the substance is almost bigger then him,we clean it 1 every week and my apaco and the other fish dont seem to be getting all the fungess that my oscar seems to be getting.. if you know anything please write me back as soon as possible i need to know whats wrong with my fish!!!!

Answer
Hi Kassidy,
 That symptom is called pop-eye and it can be caused by many things. Two of the most common are stress and poor water quality.  When you clean the tank, do you change some of the water?  You should be changing 25% of the water once a week, every week.   

 Also, be sure that you never use any soap or other cleaner in the fish tank.

-- Ron
  rcoleman@cichlidresearch.com
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