Trying to plumb off return pump for water changes...

[davidinga]

I Teed off my return pump (eheim 1262) and ran about 40ft of 1/2" ID tubing to my laundry room drain and all I can get out if it is a tiny trickel. The 40ft of tubing runs up and over the 75gal sump and down to floor level where it stays for the majority of the travel distance and then it rises to about 4.5ft to the washing machine drain. This seems like it should easily be handled by the pump but it barely moves any water.

Am I asking too much from the pump via 1/2" id tubing? Do I need larger tubing? Too much restriction from the small diameter tubing? Is 40ft too much for the pump (that seems unlikely as its flat horizontal movement for most of the distance)?

What is wrong here...?

 

[davidinga]

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[myreefclub0070]

More than likly the distance is the issue and then to clime 4 plus ft.
That pump is only rated for 11ft head but with bends, distance and tube size it just won't be able to push that far.
Over all I think it's the distance that is killing you.

 

[davidinga]

It's all static horizontal level though? Wouldn't you think a 900gph pump should work here?

 

[seth the wine guy]

Rheims are awesome pumps but they ain't worth a flip with head pressure

 

[bcavalli]

I have a valved drain line attached to my return pump, it's hard plumbed most of the way, so it's very similar to your install. It's really a simple way to do water changes out of the sump. If it's in your budget you may want to think about switching over to one of the Jaebo DCT return pumps. IMHO they are a great return pump and you can adjust the flow rate, which makes it ideal for what you are trying to accomplish.

 

[myreefclub0070]

What the pump is rated for as gph and what is actually putting out is two different things.
You could use a much shorter hose and a bucket and see how much flow you get at that point, to confirm.

 

[grouper therapy]

That much tubing at that size is probably adding at least 3' of friction loss, so you are at a total of 7.5' of loss on the very conservative side. That pump shuts down at 11 I think? The out let on that pump is around 5/8" so I would suggest 3/4" tubing.

 

[davidinga]

grouper therapy;1053585 wrote: That much tubing at that size is probably adding at least 3' of friction loss, so you are at a total of 7.5' of loss on the very conservative side. That pump shuts down at 11 I think? The out let on that pump is around 5/8" so I would suggest 3/4" tubing.

Do you think I'll get much more flow with 3/4" tubing?

 

[myreefclub0070]

I don't think you would get better flow with a bigger tube, that will just increse the water volume in the tube and be ever more harder to for the water to climb the 4 plus ft to the washer drain.
For the plan you have in mind, your best bet is a pump upgrade.

 

[grouper therapy]

MYREEFCLUB0070;1053592 wrote: I don't think you would get better flow with a bigger tube, that will just increse the water volume in the tube and be ever more harder to for the water to climb the 4 plus ft to the washer drain.
For the plan you have in mind, your best bet is a pump upgrade.

Sorry that is not accurate. The larger tube will not increase head loss but will reduce it due to less friction.
This has been proven in a thread several years back. I actually mounted a maxijet in the bottom of a 12" tube and it actually increase the flow versus a 1/2" pipe at the same height. If the area of water above increased pressure a diver could not enter the ocean. Pressure only increases as depth/height increases.
You can go to any of the other sites and use their head loss calculator and notice what happens to the head loss as the pipe size is increased.

 

[davidinga]

grouper therapy;1053594 wrote: Sorry that is not accurate. The larger tube will not increase head loss but will reduce it due to less friction.
This has been proven in a thread several years back. I actually mounted a maxijet in the bottom of a 12" tube and it actually increase the flow versus a 1/2" pipe at the same height. If the area of water above increased pressure a diver could not enter the ocean. Pressure only increases as depth/height increases.
You can go to any of the other sites and use their head loss calculator and notice what happens to the head loss as the pipe size is increased.

So... What if I jumped up to a 3/4" or 5/8" tube, would it work then?

 

[grouper therapy]

It would help. I'm not familiar with the performance curve of that particular pump. I agree with marlin that you are probably pushing the limits of that pump. That pump is the same as the 1260 but with a bigger impeller. Like seth said the when are not high head pumps. But I think it would suffice.

 

[grouper therapy]

If you think about the verical lift is probably the same as ison the aquarium or even less, thew only difference is the length of travel inside the tube and that is where the friction loss comes from. Bigger tube less friction so I would say yes it will work better. Not sure what your target GPH is.

 

[davidinga]

Update

I replaced all the 1/2"id tubing with larger 5/8"id tubing on the same 40ft run and now the same eheim 1262 pump flow like a boss. The 1/2"id tubing was clearly the bottleneck and not the pump.

 

[myreefclub0070]

DavidinGA;1055483 wrote: Update

I replaced all the 1/2"id tubing with larger 5/8"id tubing on the same 40ft run and now the same eheim 1262 pump flow like a boss. The 1/2"id tubing was clearly the bottleneck and not the pump.

Good to know, I don't mind being wrong as long as I learn and just did.

 

[grouper therapy]

DavidinGA;1055483 wrote: Update

I replaced all the 1/2"id tubing with larger 5/8"id tubing on the same 40ft run and now the same eheim 1262 pump flow like a boss. The 1/2"id tubing was clearly the bottleneck and not the pump.

Good deal.:up:

 

[grouper therapy]

MYREEFCLUB0070;1055501 wrote: Good to know, I don't mind being wrong as long as I learn and just did.

Me either .I learned early in life that I better get use to it.

 

[davidinga]

Yeah I was kinda surprised it worked now after it not working at all with 1/2"id tubing.

 

[grouper therapy]

We ran irrigation pipe sometimes close to 2 miles on the farm I grew up on. If we went that far we always had to go from 6" to 8" pipe, of course that was hooked to a pump that did 3500 gallons a minute! That pump would shoot 2 3" streams of water 300 feet simultaneously.