Maintaining My Tank

Question
I would like to know some pointers on how to maintain my fish tank of 20 gallons.First I just started my 20 gallon tank on Jan 23 2010; and I have 8 fish now out of 9. One just died today but I expected it because he was at the bottom always breathing hard and barely ate flakes. My tank consist of mollies, platys, one tetra, and one swordtail. I have a air pump that causes alot of bubbles to surface the top of the tank. Is that bad or do I turn it off? Also I need to change the filter in my opinion because it doesn't fifer a lot of gallons per hour. (120gph Aquean). What should I do? Lastly is it safe to breed fish in first stages of tank ajustment to nitrogen cycle? Can tell me what should I do maintain my tank?( tips and advice)

Answer
Hi Andy,
 The most important thing to do is regular weekly partial water changes. You should be changing 25% of the water once a week, every week to keep your fish happy and healthy.  That is more important than anything.   

 I am not sure what you mean by "is it safe to breed fish...".  The fish will breed when they want to, you cannot make them breed.  It is not too often that fish feel like breeding when they are first put in a new tank.  It typically (though not always) takes awhile for them to feel comfortable enough to breed.

-- Ron C.
  rcoleman@cichlidresearch.com
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