Some people say they are, but that's why I bought mine from liveaquaria since they offer a two week guarantee. In terms of keeping them, you need to offer loads of rubble for them to construct a house, and tops on your tank is a must since they are jumpers. I haven't ever had any issues with mine and has been eating like a piggy since day 1, oh and I target feed mine right by his little home. They usually set up fort right in the front of the tank so they can view everything. Coolest little fish I've ever had the pleasure of caring for. Had him for about 2 months now.