DIY pvc overflow flow rates

[keiths]

Does anyone know the flow rates for the diy pvc overflow? I'm looking to make an overflow like the one below but I need to figure out how much gph it can handle at 2"

Thanks

 

[dominicolas]

I would bet that 2" could handle around 1500gph max, but that's sort of a guess. Based on personal experience though.

 

[dominicolas]

Oh, and it also depends on the water level.

 

[mjohns]

Oh, and it also depends on the water level.

Yeah it wont really start to crank until its a bit above the top of the 90* bend(intake)

As long as u can hold that amount of water + a bit more youll be right.

 

[keiths]

What if I decide to not have the 90 at the top and just had the pipe. How would that effect it?

 

[mp3coupe]

I came across this during my research over the past few days. I don't know how accurate it is, if they factored in 90's but here you go
3/4" 330 gph
1" 600 gph
1 1/4" 910 gph
1 1/2" 1300 gph
1 3/4" 1800 gph
2" 2350 gph
2 1/4" 2960 gph
2 1/2" 3650 gph
2 3/4" 4450 gph
3" 5280 gph

 

[keiths]

Yea I've come across this also. I'm thinking about just doing 2 2" overflows, getting a pump that does around 2000gph and go from there. If I find my pump is too strong for 2 2" overflows then I'll just make another one.

 

[mp3coupe]

One other note, the plan you have above I've seen several posts about that design being bad? I think the output T needs to be above the lower in tank 90s. Maybe someone can confirm for the both of us

 

[keiths]

Yea now I think I'm going to use this type of plan

 

[mp3coupe]

That one seems to get praise, good luck, post results - thanks