Things (mites?) on Emerald Crab

[abcat1993]

I posted this in another section yesterday, but that one's not that busy, so:

I was looking at my emerald crab today, when I saw lots of little yellow things crawling around on it that looked like mites. Are they bad/good/do nothing? How do you kill them if they are bad? Also, it will be very hard to take a picture of them because they are .5-1 mm long, and the crab is usually in a spot that would be hard to take a picture of. Also, the "mites" seem to be only on it's claws and only on my emerald crab, not my hermits

[Paintbug]

those are some type of crustacean that lives with emeralds, and maybe some other crabs. i had the name of them, but can not seem to find them. they do not seem to harm the crabs, and are quite common. they are reddish brown, sometimes grayish?

[abcat1993]

Probably, for some reason a lot of things turn yellowish in my tank when you look at them from a certain angle.