Thing on emerald crabs leg

[nate1633]

There is this white thing on my emerald crabs leg. Yesterday it's wasn't there . My water parameters are good I just tested them what is this. Here is a pic



On the back leg ⬆️


55 gallon fowlr

[chadda8708]

can't really tell can we have a better picture?

[Cichlid-dude]

Looks like maybe a sponge growing on his leg or maybe it came off a rock on him.


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