Does any one have any experience with these? I am looking at getting a couple for my tank. Right now I have small community fish, but we are staring to build up the tank a big.nothing like what you guys have..yet lol! They said they get along well with other non aggressive fish. Im not sure how big they get though. I only have a 55 gallon right now, would this be suitable for them? Have you found the to be hardy or are they pretty sensitive?