I am currently building an algae scrubber made from .220" acrylic. I'm also making a wooden stand for it to support the base held down by nylon screws. The dimensions of the scrubber will be L=18"x H=14"x W=8"(base). It will have a 4" wide growing chamber? in the middle of the base. The screen is a roughed up knitting pattern 14"x 10". The scrubber will have a dedicated 550GPH pump with a ball valve. I'm using weld on 4 for the acrylic adhesive. I haven't glued any thing together, but have cut all the pieces to size. I am waiting on bulkheads to drill what holes i need to before glueing. This is a dumb question now, but What would be the minimum thickness of acrylic required to hold the water under pressure? I am only about $30 into this project. If i need to start over I'm not too worried about it.