Black Molly behavior

Question
A few weeks ago I purchased 5 black mollies.  They reside in a 10 gallon tank per the recommendation of pet store employee.  I believe 3 are males and 2 are females. When I first brought them home they were very active fish however recently they tend to hang out at the bottom or top of the tank instead of swimming around.  Today 3 of the mollies (1 male and 2 females) have been hiding all day inside of the cave and none of the mollies are interested in food.  I am new to fish ownership and I am not sure what this behavior indicates.  Any advice would be helpful.

Answer
Hi Becky,
  Do you have a proper filter, heater and air stone in the tank?

  Are you doing 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.  

  Also, it is essential that you remove any uneaten food, otherwise it will rot in the tank and cause your fish to eat even less, which creates more uneaten food, which rots, etc.  

-- Ron C.
  rcoleman@cichlidresearch.com
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