Have you thought about going acrylic? If you go glass with all the baffles you would be fine with 6mm (1/4") glass.

I had a 36"x18"x18" (50 gal) sump built for me a month back. The guy used 9mm glass throughout. A bit overkill for the baffles, but I think you might want to use 9mm for the tank and 6mm for the baffles. Error on the safe side. HTH. Leon

My sump set up is all 6 mm. with all the baffles siliconed in there they prevent any bowing.

BTW what stores said they can only cut 6mm? I have bought 1/2 from Benchmark and they cut it on the spot for me.

Every store here including benchmark has said they don't have someone on hand to properly cut 1/2" when I was doing my eurobrace.

That sucks. I know Bruce will cut 1/2" as well if you bring him a piece.

Theres really no need for 1/2 on a sump though 6mm will be more than enough.

Thats crazy... he was the first guy I asked about 1/2" and said he won't do it. He only said he'd order it.

I'm not planning for 1/2" for the sump. Was just wondering if 6mm would be enough, and thanks to you and a few others, I have my answer. Gonna figure out dimensions for sure tonight and get it cut.

Personally, I wouldn't do it. If you're going to DIY, go acrylic.

You may get away with it, but it's always the same story -when you consider the consequences of a failure, overbuild it. It's cheap.

Well... I've done a sump myself with acrylic already, and it's fine.. it works. It's what I'm using now, but it cost $260 just for the acrylic, and I had to cut it myself, and get weldon.. which was another 20.. So 280 on a sump, that ended up being 12" wide.. If I go bigger it will probably cost more.. And it also took a lot more time. A whole day to build. If I go buy the glass, it's already cut, I can just start siliconing it together, be done and ready for use. I just have to over silicone it, and I don't have to worry about having ANY salt seep like I do now with the acrylic.

Yeah, you will be a lot cheaper than 280. Heck the one I had built was only 225 and I didn't have to do it. Check it out.

http://www.canreef.com/vbulletin/showthread.php?t=73709

What size of glass is that?