when you say little, do you mean microscopic if you don't have 20/20 vision? or half of a fruit fly little? i'm guessing they are mites or springtails. i wouldn't use any product until you find out what it is. don't buy anything from petco/petsmart... they do nothing. they have vitimans and junk, but nothing to get rid of mites. if they are springtails just wash them off and clean the tank. if they are mites go to the vets and they will tell you what to do. springtails move a lot faster and have an elongated bottom, mites are more like little spiders and they are slower and much smaller.