Please remove the sand and get some non adhesive shelf liner or slate ceramic tile from Home Depot Lowes etc................ the tile would need to be cut to tank size so if you plan upgrading to a bigger tank I would wait on that -- the shelf liner would be a good deal now--- they are both cheap and easy to clean w/ vinegar / water in a spray bottle mixed w/ a little heavier on the vinegar side-- sand causes impaction and harbors bacteria etc................ you will like the shelf liner -- bugs cant get under neath etc...........as far as him/ her not eating its hard to say --- how old is she/ he? Why do you think she/ he is impacted? Has it been a long time since she/ he went to that bathroom?
Karrie