oscar eating rocks

Question
My 7 yr old oscar,female, just died, but just before she did, I had her in a hospital tank, and she either coughed up, or pooed out small rocks from the regular tank floor. I guess that was one of her problems. Have you ever heard of a fish doing that, and was she trying to help herself, or was this the reason she died? I have a 50 gal. tank. You should know, that I have had some serious water problems for the last several months! Right now my pH is stuck at 8.0. I am trying to get it regulated. It doesn't seem to be affecting any other fish(all ciclids). I also just bought a Fluval canister filter. Nice! a breeze to clean! Also, have had cloudy water for months. Bacteria REFUSED to grow. Finally cleared up. I added store bought bacteria, but the media in the filter is still very clean. I'd really like to see more bacteria growth.

Answer
Hi Suz,
  First, eating rocks is quite normal for oscars and most new world cichlids in general so that isn't likely the problem.

  A pH of 8 is a little high for new world cichlids.  

  However, cloudy water isn't a lack of bacteria, it is an excess of bacteria.  The cloudiness is tons of tiny little bacteria in the water.  It is usually caused by an excess of nutrients in the water, which provides a feast for the bacteria and they explode in numbers.  The solution is to make sure that your filter is working (which you have done), be sure you are not overfeeding (food rotting in the tank is a great source of nutrients) and be sure that you are doing regular weekly, partial water changes. You should be changing 25% of the water once a week, every week.  Have you been doing that?

  If I have a bacterial bloom (cloudy water) I usually do a 25% water change, and then repeat it on the next two days and that typically solves the problem.

-- Ron
  rcoleman@cichlidresearch.com
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