DIY external overflow on 20" cube

[ScubaSteve]

Not sure I follow. Are you wanting to mod an existing tank? If so, notching a built tank for c2c overflow is risky business.

But, to answer your questions...


width of over flow? I can help you calculate this but I recommend 12" to be able to handle over 800gph (over engineer)

2 pipes? Go three and do a beananimal overflow. Use gate valves for tuning the pipes.

What diameter pipes, 3/4"? No, go with 1" if you can

Water height in tank, 1.5" down (rimless tank)? That is your preference. I have my water height 0.65" from the edge (rimless). But that is a 1.25" x 12" notch flowing 600+ gph. You need to account for the laye thickness of water flowing over the weir (again, I can help calculate this).

Glass thickness, 3/8"? Yup, that's plenty thick.

[nerdz]

Originally Posted by ScubaSteve

Not sure I follow. Are you wanting to mod an existing tank? If so, notching a built tank for c2c overflow is risky business.

But, to answer your questions...


width of over flow? I can help you calculate this but I recommend 12" to be able to handle over 800gph (over engineer)

2 pipes? Go three and do a beananimal overflow. Use gate valves for tuning the pipes.

What diameter pipes, 3/4"? No, go with 1" if you can

Water height in tank, 1.5" down (rimless tank)? That is your preference. I have my water height 0.65" from the edge (rimless). But that is a 1.25" x 12" notch flowing 600+ gph. You need to account for the laye thickness of water flowing over the weir (again, I can help calculate this).

Glass thickness, 3/8"? Yup, that's plenty thick.

Thanks, yes planning on notching my brand new prebuilt tank. I don't plan to have flow over 300-400 gph. Okay, sounds like 1" pipes. Is this really necessary for this flowrate?

Cheers for the input!