my white molly fish

Question
I recently got two molly fish for my fish tank one(white molly fish) and one(black molly fish)and everything seemed fine in the tank, then about a week or two went by and I went to feed my fish and I noticed a baby black molly fish behind this big rock that I have in the middle of my fish tank! So, I guess one of my molly fish had baby molly fishes! (I counted 7 black molly baby fish) I don't know which molly fish had the babies but after that I noticed that my white molly fish seemed to stay at the bottom of my fish tank all the time just above the gravel! In the same spot, most of the time! I'm worried that something might be wrong with my white molly fish! but, my black molly fish seems to be o.k. swimming around my fish tank and the baby molly fish seem to be doing o.k. also! That's why I'm asking you if I should be concerned about my white molly fishes behavior being always down at the bottom of the fish tank hoovering over the gravel all the time?  My fish tank is a freshwater tank and always has been and their are no other fish in my fish tank besides them.I think its a 30 or 40 gallon fish tank! It sits on the top of wooden cabinet stand. Thank-you 4 reading my question! and I hope you can help me with my question about my white molly fish!

Answer
Hi Tresa,
 It is a bit unusual for a molly to sit near the bottom of the tank.  Are you doing regular weekly water changes?  You should be changing 25% of the water once a week, every week to keep your fish happy and healthy.  Have you been doing that?

 Also, the temperature in the tank should be roughly around 80oF. Colder temperatures would cause a fish to "sit" near the bottom.  

-- Ron
  rcoleman@cichlidresearch.com
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