fish nipping

Question
Hello, My tank has been set up for about 4 months. I have 4 mollies (2 old and 2 new) and 2 algea eaters.  The ph is kind of high-7.6 and the temp is around 76-77.  
I just bought 2 new mollies and as soon as I put them in the tank they starting nipping at the bottom of one of the old mollies.  It has been 3 days and though they give her a break from time to time- they just won't leave her alone.  Can you tell me why and what I should do?
Thank You!

Answer
Hi Crystal;

If the victim is a female and the aggressors are males, they are trying to breed with her. You will need more females for them to breed with in order to give her a break. She could die if she is bothered too much. Male livebearing fish like mollies are interested in breeding most of the time. It's basically what they live for. Little devils!

It is best to have at least 2 females per male. Also provide plenty of hiding places for the females to rest. Live plants are great for that. If the males can't see the females all the time they will have a few minutes of rest.

At Your Service;
Chris Robbins