Is there somewhere for it to go other than under the gravel to hide? My mercs preferred a mid water home and did not dig into the sand but the bottom substrate is much larger in this aquarium and it does not look like the animal has another place to den.
I'm afraid that what you see is what you get. The animal is kept in a small critter keeper with a bare layer of medium/large coarse gravel and one small rock in which it hides under, pressing itself agains the underside of the rock and completely covering itself with the gravel. It was really amazing that it could cover every centimeter of it's body with gravel. I literally could not see the animal. I only knew it was there as the gravel would giggle as the store attendant rotated the rock. They really don't know how to treat the animals they recieve and do not know anything about identifying and/or caring for them. I guess I can understand though, with too much debris in the container you would not be able to see the animal and since their goal is to sell it it would be unwise to allow it to hide to well. Though this animal does have it better off than some. I've seen animals before that only had gravel and were kept in a clear container. Judging by it's size I would say it's almost full grown or close to it. Since I have never kept a merc before and have not read too much about them for lack of interest I cannot be certain. But the mantel is about the size of a small/medium grape.