I'm going to buy and cut some acrylic for a 20g long sump. Want to be sure I buy it thick enough to not warp (as experience tells me that 1/8" thick will warp!). I'll probably do this in 3 sections so that I can slide a section over another to expose an opening without having to actually remove the cover except when necessary to gain full access.
20g L dimensions are: 30" x 12"
Hoping someone has already done this and can share their experience.