DIY adjustable water level overflow?

[gravereaper0]

I'd like to have an adjustable level overflow using two pipes in a "Herbie" setup (like joey's 150 gallon acrylic tank build), but can't really think of a practical way of doing it. Anyone ever seen one or know where I can find some schematics?

[fiesta90150]

can't you just have a one peice of tubing slide up and down the inside or the outside of another one?

[gravereaper0]

But how do you make it water tight

[gabrieltariman_03]

Or just have a few different length size of pvcs that are not glued together. Pvc pipes are pretty snug even when not glued in. Some doesn't even glue their overflows that goes in the tank. You can just pop one out and put a shorter or longer one in. And why do you need one with adjustable overflow? Do you have a weir? I'm sorry if I translated the question wrong.

[gravereaper0]

I want the pipes to be as close to the back corners as possible and its an acrylic tank so its braced. So for me to fit em under the braces and have the water level about a 1/4" away from em I would have to install em and then raise em. By the way, what's the minimum safe distance from the corners and each other to drill two 1" holes on a 1/2" thick acrylic?
I was thinking I'd just put one pipe inside another and where the pipes meet clamp a rubber sleeve over them?

[thelub]

I don't know about acrylic, but with glass you never want to be closer than the diameter of the pipe to any edge or hole. I would imagine that would be a good rule of thumb for acrylic as well.

[gravereaper0]

Siliconeintakes.com has reducers/couplers of all sizes so I believe I can make my idea work.

[gabrieltariman_03]

Why not drill on the side of the tank if you want it to take less space in the tank? If you're doing durso or herbie standpipe, They can go to the side of the tank. That way you can use a bulkhead with slip fittings and street elbow fitting. Bulkreefsupply.com have a video on youtube about herbie overflow. Watch the whole thing.

[gravereaper0]

I don't want a black overflow box sitting in the corner of the tank.

[Divinehammer]

yup you have to keep it away from the edge, you also have to take into account the bulkheads size on the sealing flanges, so in all reality you will need that hole minimum 1" from the corner on both sides, and you are not going to want the stand pipe 1/4" from the brace or you will have water over top of the brace, in most case for the overflow to work correctly the water level is 1/2-1" above the top of the stand pipe, otherwise you get the toilet flushing sound.