silver doller fish

Question
i was wondering what is wrong with the silver dollars in my big tank as they seem to be gasping for air and it sort of looks as if their top lip is missing or just the bottom lip is swollen.They keep swimming up to the surface and gasping for air. The tank hasn't been cleaned in a while so is it that and also there is also a red devil, ciclid and some barbs in the tank so are they just fighting? i would really like to knoe ASAP!! Thank you

Answer
Hi Tanya,
 It sounds like you have several problems. Yes, they are likely fighting.  But, equally important, you need to change 25% of the water in the tank, once a week, EVERY week, to keep the fish happy and healthy.  Letting the tank go for awhile and then doing a "big clean" is actually a recipe for disaster.  

-- Ron
  rcoleman@cichlidresearch.com
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