Overflow / Gravity GPH Question

[Stevorino]

For my new build, my sump will be on the wall behind the display tank. All of my previous sumps have been entirely below the display.

I understand that if the water level of the sump is below the water level of the display, gravity will pull the water from the display overflow to the sump without a problem.

But does the water flow at a higher rate the lower I drop the sump.... and how much of a difference are we talking?

Essentially I am trying to figure out if I can put my sump on a piece of cabinetry/furniture without sacrificing too much gph from the display.... or if I need to place the sump lower to the ground to keep up the gph from the display.

Thanks in advance!

 

[KStatefan]

Yes the flow will be reduced.

 

[FUNGI]

https://www.omnicalculator.com/physics/pipe-flow

 

[Pntbll687]

For my new build, my sump will be on the wall behind the display tank. All of my previous sumps have been entirely below the display.

I understand that if the water level of the sump is below the water level of the display, gravity will pull the water from the display overflow to the sump without a problem.

But does the water flow at a higher rate the lower I drop the sump.... and how much of a difference are we talking?

Essentially I am trying to figure out if I can put my sump on a piece of cabinetry/furniture without sacrificing too much gph from the display.... or if I need to place the sump lower to the ground to keep up the gph from the display.

Thanks in advance!

Put the sump on a stand! Make your life easier when doing maintenance in the sump.

There will be reduced flow, but you could just oversize the pipes to get to the flow you want. If the bulkkheads on the tank are 1in, then reduce at the bulkhead and use 1.25 or 1.5" pipe.

The difference between a tank in the bainet, and one on stand is probably not going to be a measurable difference in this case. You'd see a much bigger difference between say a sump in the cabinet and a sump a floor below in a basement.

 

[Stevorino]

https://www.omnicalculator.com/physics/pipe-flow

Super helpful - thank you!

 

[Stevorino]

Put the sump on a stand! Make your life easier when doing maintenance in the sump.

There will be reduced flow, but you could just oversize the pipes to get to the flow you want. If the bulkkheads on the tank are 1in, then reduce at the bulkhead and use 1.25 or 1.5" pipe.

The difference between a tank in the bainet, and one on stand is probably not going to be a measurable difference in this case. You'd see a much bigger difference between say a sump in the cabinet and a sump a floor below in a basement.

I think you are spot on with all of this.

The calculator posted by @FUNGI is really interesting - there's a pretty big jump in gph from even 1.5 ft to 2ft.

I have two 1" and two 3/4" bulkheads to work with. I'm thinking if I do full siphon on the two one inchers, a durso, and then emergency line for the 3/4, I can move enough water to max out my rollermat throughput.

Two other questions:

- Is a Bean Animal with two siphons the best approach here for the overflow?

- Am I right that if I continue the pipe into the sump to go down below the water level and near the bottom of the sump, I get more velocity from a gravity perspective, than if I just have the pipe end when it's just below the sump water level?

My sump is 18" tall, so I'm thinking that can buy me another foot of distance/velocity.

 

[Pntbll687]

I think you are spot on with all of this.

The calculator posted by @FUNGI is really interesting - there's a pretty big jump in gph from even 1.5 ft to 2ft.

I have two 1" and two 3/4" bulkheads to work with. I'm thinking if I do full siphon on the two one inchers, a durso, and then emergency line for the 3/4, I can move enough water to max out my rollermat throughput.

Two other questions:

- Is a Bean Animal with two siphons the best approach here for the overflow?

- Am I right that if I continue the pipe into the sump to go down below the water level and near the bottom of the sump, I get more velocity from a gravity perspective, than if I just have the pipe end when it's just below the sump water level?

My sump is 18" tall, so I'm thinking that can buy me another foot of distance/velocity.

Normally people use the 3/4 as the full siphon and the 1in as the emergency. This way of the full siphon gets clogged the emergency can handle all the flow. If you run it the other way, if the siphon gets blocked you run the risk of flooding the tank because the 3/4 drain won’t be able to keep up. At least that’s how people used to run them where they convert the corner overflow to a herbie drain.

You may get more velocity gashing the pipe all the way to the bottom of the sump, but you may end up with some gurgle noise. That’s something you’ll just have to play with with once it’s set up.

As for the reefmat, I’d get a pump dedicated to running the reefmat.