my fresh water fish tank

Question
Hello Mr Coleman,I have a 50 gal fresh water tank that has been set up for about 6 to eight weeks. I have a peguin 350 b bio wheel filter on it two bubblers going one at each end and have 1-3inch gold fish  1-2 inch gold fish 2 feeder gold fish 1-fan tail gold fish one black shark bottom feeder and had two pleco sucker fish. Just got rid of one yesterday for he had a bulging eye and could not attach to anything like usually was just there would not hide and just kind of there later in the day i found him by the filter port not stuck to it but close touch him he would move and things but looked like he was not going to make it. tested my tank water and everything tested good according to the stripes we use due to being worried about the rest of the fish in the tank i was asked to remove the fish asap by my wife someone that most of the time i do not say no to I just do not know what to do i am worried about the rest of the fish we do have.should we do a water change should i treat the tank with it ich meds. The day before this happened i scrubed the walls down a little they had some algea growing but did it very slow the fish didnt mind me there they were swimming close to the brush and my hand and were not scared of it or me. I do not know please give some suggestions if you can help would be great thank you for your time Steve.

Answer
Hi Steven,
  You should be changing 25% of the water once a week, every week. That more than anything will help keep the fish happy and healthy.  I would not put in any medicine (ick or otherwise) unless you know that the fish have that disease.  Fish medicines should never be used "just in case". They often cause more problems than they solve.

 The problem with the catfish was likely caused by an attack from one of the other fish.  

-- Ron C.
  rcoleman@cichlidresearch.com
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