I have had my Red claw crabs for a week with no problems. Today 3 of the 4 crabs were very still somtimes on their backs. 1 died. the water level is quite high with little chance for them to get out into air. I wondered if they were drowning so I made a platform for the others to sit on 1 seems to have died but the other looks much stronger now. I also think the first crab to die had eggs as there was a red jelly under it. One of the crabs keeps opening a sort of flap underneath itself. Any advise on how to keep these properly would be good.