Crab Question

[Robbrcub]

Hey, guys. I'd like to get some opinions on my emerald mithrax crabs. I bought two at my LFS when I first started cycling my tank. I really like them a lot, but I've heard of these types of crabs becoming aggressive to other tank inhabitants. Last night after work, I had the actinic on and was watching my cleaner shrimp. I was interested cause he was hanging out on a different piece of LR than normal. What caught my attention was one of the crabs sort of camouflaged in a hole with one arm sticking out. Any time the cleaner shrimp would come near, the crab would wave his claw quickly in his direction (attack mode, I'm assuming). Anyway, although I have not had any problems with these guys before, I'm considering getting rid of them. I'd appreciate any thoughts or similar stories you guys may have. Also suggestions on how to dig them out of a pretty holey piece of LR..LOL. Thanks,

Robb

[tdwyatt]

Hi Robb,

Welcome to TRT!


I would not worry about this type of behavior for the crab, it is defensive for the crab more than anything. This is not to say that it would not eat the shrimp given the opportunity, but chasing down the shrimp would not be normal (maybe if the shrimp had just molted and the crab was really hungry... ) These crabs are usually opportunistic feeders, cleaning up left over food and grooming the rock for microalgae and miscellaneous tidbits the crabs come across. Check the chelipeds for flat tips, one of the hallmrks of the species of crabs ( Mithraculus sculptus ) you want for your tank.

btw, Mithraculus has been recently established as a new genus for the smaller members of the old genus Mithrax, and even then, there is much variation in color and general appearance within the specie.

[Loverotties]

Never had problems with them,he just holding his ground.

[Robbrcub]

Thanks for the advice, guys....I really didn't want to have to get rid of them.

[whatevva]

I just put 4 of these guys in my tank and I LOVE watching them!! They're like little munching robots.