I've got sugar sized sand about 2-21/2" deep. Mine "remodels" my sand bed often. It will often go to the bottom if there are lot's of "yummies" in the area he's working. Make sure your rock piles are secure too, they'll work around and under them if they can.
They do jump, I fished mine out of the overflow 3 times in the first week. But I have a canopy, so he never made it to the floor. Very skittish fish. But it eats anything that hits the bottom, flakes, pellets and anything frozen.
Great fish to watch work
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