$800 seems a bit steep. Are you getting this price from a local plastics supplier? My local plastics supplier has .708 thick Acrylite GP listed at 14.02 per sq ft on their website. Although I'm not sure how accurate the price is or how often they update their website price list. But $14.02 X 32 sq ft = $448.64 per sheet.
I'd keep an eye on the crab and keep him well fed if you plan to keep him. Although it would be high on my list of suspects if something was to get eaten. Maybe he would taste good with some lemon butter sauce!
