Red Claw Crab Help Please

[slick328]

My son got a red claw crab on jan 4th for his birthday and then two more on the 9th at his party.noticed the first one was alittle bigger and became alittle dominate.one of the second claws soon had a claw and a leg missing figured the bigger one was fighting it to dominate.last week the two crabs bought second were dead in the tank.last night I feed and watched the bigger one eat but this morning I noticed there was a leg and both of his claws laying on his boat.so over night he lost a leg and both claws they are not hung up in anything looks like they just fell off.starting to think it has been a problem all along and the first other ones were also sick and loss of limbs was not from fighting.tank is keeped around 74-75.they have land acess.can anyone help.these were my sons birthday and I'm worried I might have done something wrong.

 

[raptorrex]

My son got a red claw crab on jan 4th for his birthday and then two more on the 9th at his party.noticed the first one was alittle bigger and became alittle dominate.one of the second claws soon had a claw and a leg missing figured the bigger one was fighting it to dominate.last week the two crabs bought second were dead in the tank.last night I feed and watched the bigger one eat but this morning I noticed there was a leg and both of his claws laying on his boat.so over night he lost a leg and both claws they are not hung up in anything looks like they just fell off.starting to think it has been a problem all along and the first other ones were also sick and loss of limbs was not from fighting.tank is keeped around 74-75.they have land acess.can anyone help.these were my sons birthday and I'm worried I might have done something wrong.

its a hard one this. but, are the crabs in brackish water?
can/do you see the "first" crab?
spontaneous limb dropping, is not something common to Redclaw crabs. neither, in my experience, is aggression towards each other. you say they have acces to land. thing is, they need acces to water. as they live, predominantly, live on land.

could you tell me the tank size, substrate (gravel/sand/bare). type and model of filter. and other, if any, occupants, of the tank.
any, suggestion, as to the cause. would be no more than a guess, at the moment.

 

[betta fish]

Are you sure the crabs aren't just moulting and this is infact their shed skin? I used to keep red claws and when they moulted I always thought they had died but they would then turn up a few days later looking bigger but fine! have you actually seen the crab without the claws or just the claws assuming that they fell off? the crabs will often eat the skin they shed too, search the tank thoroughly and look in decorations etc to see if you can find the others, the only sure way of telling if it is a dead crab instead of skin is by smelling it, a dead crab will smell really bad