arrrh, there be crabs in thar waters

[Tau2301]

I was at Big Al's last night and I must admit they had a very large selection of fish. Of course they had some of the unethical variety, but I am sure it is what just came with the stuff they did order

What they had that interested me were the crabs. The tank labels read; porcelin crab. sally lightfoot, green mithrax, and red mithrax.

As I run a deep sand bed with a variety of creatures, some I bought and some that seem to appear out of no where. I am curoius to know if any of these crabs will harm/consume my current critters.

Spagetti Worms, Bristle Worms, Pods, various snails, and fighting conches.

I have had a green mithrax in the past, but my six line wrasse took great delight in dragging it around the tank and them picking out it's soft bits.

Any experiance or lore about these crabs?

TIA