Question with color and how to know if a crab is "burying"

[crazykidsdad]

Okay - I saw some similiar post but not sure if this follows under any.

First - how do you know if a crab is just sleeping in its shell or molting? Our crab just sits in his shell most of the day, doesnt move around much unless I put him outside. My 6 year old always wants to pick him up and see what he is doing. This process usually he starts to come out of his shell. Today - the crabs body was almost white, claws reddish - purple. He looked sickly.

What is this caused from?

Also, is it okay if they do not eat for days? Could the crab be molting? Should we worry if it doesn't look like it is doing anything?

Thanks!

[CrabbyJo]

It sounds as if your crab could be heading for a molt. They tend to become a gray/ashy color as the old exo begins to separate from the new exo underneath. I suggest you stop handling him and try to minimize disturbances. Has he shown any signs of wanting to dig?
What kind of substrate do you have, and how deep is it?

Yes, it is normal for them to not eat for days, or to not appear to. Sometimes they are munching on their substrate, such as eco earth, or on wood in the tank.

It does sound, though, like your crab may be heading for a surface molt. If you have other crabs in the tank, you will want to make sure he is separated off from them, either with a divider or if you have the means, set up a separate tank for him (an isolation tank). It should have conditions that are the same as the main tank. If not possible, you can use something like the glass from a picture frame to push down into the substrate to keep other crabs away from him. Keep in mind that you don't want to have climbing plants or toys that may allow other crabs to get over the divider.

Make sure he has a good supply of calcium rich food (such as crushed cuttle bone or crushed egg shell) and protein such as freeze dried shrimp and some seaweed sources (like spirulina).

He will also need his own dish of fresh dechlorinated water and ocean salt water.
Others will have advice for you soon, I must rush off to work! Good luck!