Brittle stars are extremely hardy. They can be exposed to air and never miss a beat. If you are going to be keeping fish in the tank with them, I suggest that you steer clear of the Green Serpent Stars. They will eventually kill every fish in your tank. They are predators to the fullest extent. If you keep them with fish, eventually your fish will have scratches on them from being attacked and then one day your fish will vanish. Trust me, I know from experience.