Remove them and take them back to the fish store. Your tank is not ready for the animals, too many animals. In a 14 g I would only recommend two clown fish, no other fish, no hermit crab, or star fish. In fact nothing else that you have to feed.
There was no ammonia source before, so the biological filtration did not developed. Now you added all these animal that put out ammonia, the tank cannot handle it.