How much GPH can a 1" drain bulkhead handle?

[Reefer08]

How much can a 1 inch drain bulkhead handle? I think I read somewhere its 300gph but im not 100% sure.

My drain is draining at a rate of 288gph (I timed it). Just wanted to see if it could hande anymore going through it. Thanks

[saltjohnswharf]

To the best of my knowledge a 1" bulkhead can release 300 GPH using gravity alone when unobstructed by filter screens.

[cham]

My last two tanks have had a single 1" bulk head that has handled the return from my 2500 gph reeflo snapper. With head loss I imagine it was handling close to 1800 gph. So anything below 2000 gph is good.

I've valved my snapper way back since then but I had it running that way for several months.

[saltjohnswharf]

Originally posted by cham
My last two tanks have had a single 1" bulk head that has handled the return from my 2500 gph reeflo snapper. With head loss I imagine it was handling close to 1800 gph. So anything below 2000 gph is good.

I've valved my snapper way back since then but I had it running that way for several months.

You are basing this on how much water your pump puts back into the tank? My pump at the top of the output is pumping 615 GPH in but at the bottum of the sump inlet it is rating about 300. The water in the overflow is always lower than the tank level because the pump is putting water back in faster than the water comes out. I think I am confusing myself now. I think the only thing to do is use a proper pump with a control valve and adjust until the sump level equals out. No matter how much water flows through the bulk head. Sure gets me thinking though!

[cham]

Originally posted by saltjohnswharf
You are basing this on how much water your pump puts back into the tank? My pump at the top of the output is pumping 615 GPH in but at the bottum of the sump inlet it is rating about 300. The water in the overflow is always lower than the tank level because the pump is putting water back in faster than the water comes out. I think I am confusing myself now. I think the only thing to do is use a proper pump with a control valve and adjust until the sump level equals out. No matter how much water flows through the bulk head. Sure gets me thinking though!

Basically yes, my snapper runs about 2500 gph. With some head loss 1800 gph is a generous guess at whats being put into the tank. Unless there is a genie in my tank, what goes in must come out.

I do have an emergency drain but its rarely used. People are always suprised that a 1" can drain 2000 gph.

[saltjohnswharf]

Originally posted by cham
Basically yes, my snapper runs about 2500 gph. With some head loss 1800 gph is a generous guess at whats being put into the tank. Unless there is a genie in my tank, what goes in must come out.

I do have an emergency drain but its rarely used. People are always suprised that a 1" can drain 2000 gph.

I know I am surprised. I would be tempted to try it but I do not need that much pouring into my sump.

[Imzadi]

I can pull about 1500gph on my 1", but it is only about a 3' drop on the siphon. If you were going to a basement sump on 1", I bet you could pull some high numbers. Cham, how long is your pipe?

[cham]

I'm droping close to 5'

[Paramecium]

Originally posted by saltjohnswharf
You are basing this on how much water your pump puts back into the tank? My pump at the top of the output is pumping 615 GPH in but at the bottum of the sump inlet it is rating about 300. The water in the overflow is always lower than the tank level because the pump is putting water back in faster than the water comes out. I think I am confusing myself now. I think the only thing to do is use a proper pump with a control valve and adjust until the sump level equals out. No matter how much water flows through the bulk head. Sure gets me thinking though!

You just confused me. If your putting 615 up and draining only 300 your going to flood the tank fairly quickly. Did you actually measure this or are you basing it off of a head loss calculator? I believe most 1" overflows are rated at about 600 gph. From my experience Durso style drains work better as 1 1/4" adapted down to 1" at the bulkhead. As for how much they "can" drain. If you get them on a siphon you can move an incredible amount of water through them. Of course the air holes in the top of the Durso prevent this from happening if it is setup right. Put your finger over the hole though and watch how fast it sucks the water out of the overflow box. I'm running an Eheim 1262 back to my tank with no restrictions and easily draining through a single 1" bulkhead.

[Imzadi]

I wonder if there is a chart somewhere to calc that. A couple extra feet of pipe, and 500gph more.

[Paramecium]

Some others chimed in while I was typing. Cham and Imzadi. Those are some good numbers. Like I said you can get a ton of water through them on a siphon. And most pumps are probably returning less than you think even with head loss calculators. Unless you actually measure it you can be off a fair amount I imagine an estimate.

[saltjohnswharf]

Originally posted by Paramecium
You just confused me. If your putting 615 up and draining only 300 your going to flood the tank fairly quickly. Did you actually measure this or are you basing it off of a head loss calculator? I believe most 1" overflows are rated at about 600 gph. From my experience Durso style drains work better as 1 1/4" adapted down to 1" at the bulkhead. As for how much they "can" drain. If you get them on a siphon you can move an incredible amount of water through them. Of course the air holes in the top of the Durso prevent this from happening if it is setup right. Put your finger over the hole though and watch how fast it sucks the water out of the overflow box. I'm running an Eheim 1262 back to my tank with no restrictions and easily draining through a single 1" bulkhead.

I was using a flowmeter that was slip knotted onto the drain and output. I realize it should equal flood. Either that or it equals bad flow meter. It really is not important to retest as the sump is level and the drain is flowing cleanly. I guess I will have to do some more reading on the subject myself when I set up a new sump. Perhaps a better flow meter while I am at it.

[Paramecium]

Never used a flow meter on a tank but I deal with them on a much larger scale at work all the time. Only thing I can see that would make a big difference is that on your return it should be a solid head of water while the drain is air/water draining and that may mess with the meter. Like I said I'm going on a general flow meter knowledge here but in my experience they are setup to measure one thing accurately. Either gas, liquid etc. I'm assuming this is something fairly simple whereas the ones we use can be fairly complex. Some are set for a certain specific gravity while others are variable etc.

[Paramecium]

Are you using something like this?



http://www.drsfostersmith.com/produc...m?pcatid=14681

If so I would think that the drain wouldn't read correctly. Like I said it would read more accurately on a pressurized line that was liquid full rather than something draining a mixture of turbulent air and water.

[saltjohnswharf]

Originally posted by Paramecium
Like I said I'm going on a general flow meter knowledge here but in my experience they are setup to measure one thing accurately. Either gas, liquid etc.

There was noticeable air in the drain and none in the return. I feel kinda dumb now. Derrrrrr

[Paramecium]

No reason to feel dumb. If I didn't work with the stuff every day I would have no clue. I just know that when we get hot gases flashing in the line or a vapor pocket in a system it can throw the meters out of whack.

[saltjohnswharf]

Originally posted by Paramecium
Are you using something like this?



http://www.drsfostersmith.com/produc...m?pcatid=14681

If so I would think that the drain wouldn't read correctly. Like I said it would read more accurately on a pressurized line that was liquid full rather than something draining a mixture of turbulent air and water.

I purchased the meter from the hardware store. It is made from PVC and has a dial on if like the air pressure meter on a bike pump. There is a clear section showing you where the water flows through. The guy at the store said it would help me. I spent $20 each on them and now I wish to just throw them away. They did not help set up the sump at all.

[Paramecium]

I guess it's nice to know the numbers but like the others said, you'd have a hard time overcoming that drain. When I set mine up I just let the return run full blast and then watched the tank to make sure it wasn't filling up above the drain. You'd have to be running a pretty serious pump to make it a cause for concern I would imagine.

[Imzadi]

Take a peek in my 'Red House' thing... I have a couple videos of my siphon kickin in. It really is remarkable.

[Nanook]

http://www.reefcentral.com/calc/drain.php

[Nanook]

1" bulkhead will handle about 900-1000gph by gravity drain.

[Reefer08]

No need for a flow meter. Just get a 1 gallon jug and see how many seconds it takes to fill that up and divide by 3600. Thanks for the link Nanook. Looks like I need a faster return pump!