Plexi will work but it's not cheap.. Check out menards and home depot.. They have clear acrylic sheets that are just as strong but not quite as much.. Ive yet to get my snake but I feel I'm creative and being a mechanic I'm mechanically inclined so to speek.. U don't really glue the plastic you bond it.. Check out hobby stores for "plastruct" or there's a product u can buy online called weld on.. Basically both products are the same and they weld the plastic together..

Ftee getting your form down put some aquarium safe silicone in the corners and drill some holes for air.. I'm currently trying to "trim" mine with aluminum right angle bar stock but having a hard time fastening the alum to the plastic.. A little light sanding and loctite go2 glue seems to have done it tho.. I'll b posting pics in a couple days once everything is cured

Oh and btw my lil project cost me 40$