(no subject)

 I have five pond snails.  I have two very tiny babies, two medium, and 
one very large one.  I got them from science class.  They are living with 
four guppys.  I have a question.  The big snail keeps on tugging at the 
smaller snails shells.  I don't know why this is happening, or how to 
stop it.  Please write back.  Also, I was wondering if it is actually 
okay to feed them guppy food.