Building a sump/refugium

[cc_bruno]

I'll be getting some 1/4" thick acrylic this week, and was wondering what the tallest sump I could build with it, both with, and without cross supports along the top. The sheets are 50"x75", and was thinking of making it a sump/refugium, that measured 18" tall, 24" wide, and 72" long, with each being half of the length, (so, a 36" long sump and a 36" long refugium). Thanks in advance for your help.

Regards,
Robert

P.S. I don't know if it's cell cast or extruded, so, let's assume extruded, and go worst case.