From experience, there are your nippers and your non-nippers. The nipping thing is up to the individual... it varies from fish to fish. I had a few in a 55 gallon that never nipped a thing yet I hear people talk about nippers all the time so there's no doubt they are out there. Some get these little guys and find that they are hard to feed, which is because they sometimes refuse to eat or don't realize they can eat something other than snails which may not be so readily available for everyone. If not readily available, frozen blood worms and brine shrimp worked well for me. Also, a lot of time, in the trade, you will find a lot of these little guys have bacterial infections which is another reason for their refusal to eat, a lot die soon after purchase. BUT all that said, they are a wonderful little fish with lots of personality and I would recommend if placing in anything smaller than a 55 gallon, make it a sopecies only tank, aside from maybe your algae eaters.