Molly Dalmations

Question
I have a 20 gallon tall tank...we just got a few different, what I thought was non-aggressive fish. 2 Molly Dalmations, 2 black phantom tetras, 3 neon tetras, 4 tiger barbs, a catfish, and a pleco. The most aggressive is my white molly dalmation. Every day we looked in the tank we were missing fish...they were not sucked up in the filter/pump. So I thought they were jumping out. Couldn't find any, all the while my molly's belly kept getting bigger...and then I saw her picking on the others she killed my catfish and my black phantom tetra...I don't know about the others I'm only guessing. I am down to 1 black phantom tetra, 1 neon, 2 tiger barbs, and my pleco. Is it normal for them to pick and eat other fish, she not that much bigger than the others. I can't think of anything else...except what I saw. Please let me know I'm very unfamiliar with these type of fish. I have a 55 gallon long with cichlids...I know how aggressive they are supposed to be, I have a red devil and a green terror. Please help with any info you can give. Thanks for your time.

Answer
Hi Kristie,
  While it is possible that the molly is attacking the other fish, more likely they are weak and she is just finishing them off.  The fact that her belly is getting larger is likely a coincidence.  Like all mollies she is probably pregnant.  Mollies only need to mate once and then they can store the sperm for a long time and use it to produce many batches of kids.  

-- Ron
  rcoleman@cichlidresearch.com
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