DIY sump help

[ksicard]

Hey all,
I'm about to re baffle my sump that I made some time ago because I did a slop job the first time around and my plexiglass baffles just aren't going to cut it. This time around I wanted to get some glass cut from a glass cutter for my baffles. The problem is i'm not sure what size baffles I should get cut. I don't know the inner demisions of my sump and am afraid that I'll get my baffles cut to small or to big for the sump. The sump itself is 30"x 12 1/4". Is there any trick to measuring out the inner demisions so I don't get the wrong size baffles cut width wise?

 

[Young347]

Yes measure the outer diameter and then measure what thickness the glass is probable 1/4 or .25 thick glass then subtract 1/2 in for the length but make sure you also subtract say 1/8 of an inch or even 1/4 of an inch for the baffles you do want a little gap in all sides of the baffles when you silicone them in place you can use tape and zip ties to gap the sides and bottom

 

[sleepydoc]

Better yet, take two flat pieces of scrap wood that are shorter than the dimension you want to measure. Hold them inside the tank so each has an end on the walls you want to measure. Clamp them together, remove them and measure the length. Subtract ⅛" for the cut to give a 1/16" gap on either side. Check with the glass cutter as to what his/her tolerances are, but IME they are usually within 1/16"

I'm assuming your sump is glass - is it a glass aquarium, or a custom sump?