Crab Molt - Can He Eat It?

[JSM]

I have a very large dardanus megistos, he's the red crab with the white spots, he's in a 150g by himself. They bury their molts to go back to eat them later like mantis do, I usually take them out thinking it would foul the water because they would start to decay, but I got to thinking, he probably wouldn't eat something that was decayed, I know the ocean is much bigger than his tank but if his exoskeleton is made of some type of calcium, would it degrade quickly?

Janna

[Randy Holmes-Farley]

If it is big and easy to remove, I'd do it. But I almost never remove shrimp molts myself.

[JSM]

He's bigger than my fist so he is pretty big. I always feel so guilty taking it out because he comes running after me trying to get it back. I never take shrimp molts out either, I can never find the mantis molt but he is much bigger than a mantis. I was just wondering what it is made out of, I was assuming something calcium based???

Janna

[Randy Holmes-Farley]

No, it is not mostly calcium. Such materials are usually organic polymers such as chitin:

http://en.wikipedia.org/wiki/Chitin

If you feed him, he doesn't need to eat it. :)

[MayorOfWhoVille]

I have a reef lobster and some shrimp and when they molt it gets eaten within a day. Everything in my tank seems to have a love for molting, the fish, snails, crabs, shrimp and lobster all eat the molt. I don't remember where I heard this, but for some reason I feel like they either recover some nutrient or micronutrient. If the crab seems to take care of the problem himself, I personally would probably just leave it in there, but not if it just sits there and he doesn't eat it. I wouldn't think there would be any risk of it fouling the water, but who knows.