I just wanted to relate my latest experience with some red clawed crabs that I purchased. I had a well established 55 gallon tank that contained 5 black neon tetras and 3 peppered corys. From what I read crabs are too slow to catch fish so I decided to give it a shot. Within a day of placing the crabs in the tank, one of my corys was dead. The next day two of my black neon tetras and another of the corys were dead. I immediately removed the crabs and put them in their own tank. I noticed on the remaining cory that it has a big red splotch near its head. I suspect this was from a claw since it has been healing nicely of the past several days. I suspect the crab were catching the fish by hiding inside of a piece of driftwood and waiting for the fish to swim under it (it forms a small cave). As the fist swam under it, SNAP. Dead fish. Since I moved the crabs I haven't lost any more fish and have added others but the original tetras are still acting a little freaked out.