was looking into the already built HOB overflows but if i can make one for cheap i would rather do that, any decent ideas or does any one have any knowledge about them?
you building a snail guard or something for that guy? what happens when a large snail sits right on the screen and blocks/impedes flow and your return pump is still going at its rate and then dry?
that's what i used, too. i scored the surface with some light sanding and primered first for great adhesion. the stuff dries fast, too in proper temps and has held up with multiple coats in the tank even against scratching and bumping of rocks when aquascaping.
Unless I have a design flaw somewhere it is very sensitive to the rate of return from the pump. I have a 950gph turned down to what seems like a trickle.
The drain is just the vertical pipe with no elbow on it. Could that be the reason?