yeah i wouldnt do a sump shorter than 10" tall and 12" wide
my bad i could have sworn all those said 1/4 when i read it
Guy has a bunch of 1/4" plexi sheets in grey, clear, yellow, black, said he's looking to get rid of it all, might make some good overflows and sumps etc
http://tricities.craigslist.org/mat/3300167699.html
Oh i see the 1/4" at the bottom, it's black acrylic, and only 7.5" wide, that means your sump could only be that tall...:/