why does my molly do this

Question
Thank you for answering my last question it was really good information. Anyway I have 2 female molly fish and 1 of the females is a balloon molly and the other is a marble molly and i have 1 balloon molly male. The marble female is chasing the male around the tank none stop! She keeps on going underneath the male and rubbing her nose against the fin that shows the gender.What is she doing and why is she doing that(we gave them brine shrimp twice a day for 1 week).

Answer
Good evening Buddy, thank you for your question.

This sounds like spawning behavior, in this case your female is the more assertive of the pair. Livebearers never seem to stop attempting to, er, bear live! Nothing to worry about, except perhaps wondering what to do with all the fry, unless they are consumed by their parents...it happens!

Brine shrimp is so palatable to fish, I give mine a little frozen now and then. My favorite is the spirulina or vitamin-enhanced frozen kind, since if you look on the back of frozen brine shrimp, the nutritional analysis concludes: 6% protein, 92% moisture. Hmm, not the most nutritious...

So do keep feeding your mollies their flakes, Tetra makes a spirulina kind that mollies especially enjoy, and it is very good for them. Also try bloodworms, frozen or live, for variety. Frozen mysis is a fine supplement to brine shrimp, and much more nutritious, you can even smell the difference.

Check out this page on molly reproduction for more info:
http://www.wetwebmedia.com/FWSubWebIndex/mollyreprofaqs.htm

Good luck, ole' Buddy ole' pal, write back anytime.
Nicole