Sump fluid dynamics?

Fourstars · Dec 14, 2019

I have purchased a new SCA 150 gallon tank and I’m in the planning process. I’m planning to have a remote sump in my utility room on the same floor. The bathroom between the tank and utility room has a raised floor and I can run plumbing under floor into the utility room. My question is if I run the plumbing to floor level and under the bathroom floor can I then run it up to any level I want as long as it’s under the level of the DT over flow. I would like to have my sump up As high as possible to maintenance easier.

don_chuwish · Dec 15, 2019

Are you talking about going down, then up, and down again? It'll drain as long as the end of the drain lines are lower than the overflow box. But keep in mind how WELL it'll drain. How much net fall would you have?

Quietman · Dec 15, 2019

I would run some hose same diameter as planned pipe. Simulate the elevation change in your garage or outside. See how much drainage you have. No doubt you can move water with big enough pump. Id also be worried about back flow overfilling tank if higher.

ca1ore · Dec 15, 2019

No problem for the return, but gravity drains generally don’t appreciate upward runs. It may not restart properly. I wouldn’t do it.

Fourstars · Dec 15, 2019

Thank you for the replies. I would drop about 4 feet from the overflow then under the bathroom floor and back up about three feet to sump. So I guess net fall is a foot. The run under the bathroom floor is only about six foot. In principle it should drain fine but wondering if I’m over looking anything.

Fourstars · Dec 15, 2019

Just missed your post ca1ore. Didn’t think about restart good point! I think I might redesign and keep sump at floor level

Auquanut · Dec 15, 2019

You might consider return pressure as well. Every 90 degree angle you add to the return plumbing will drop your return pressure. You can compensate with the GPH value of the pump, but just something to factor in.

WVNed · Dec 15, 2019

If it goes down and then up it will be fine. I am running mine through a wall and have about a 16 inch difference between level the sump and level in the overflow.
It is goes down then up then down it will trap air.
I ported my drains into the bottom of my sump with bulkheads.
I am flowing about 3500gph through this.

You do not need a lot of height difference. A HOB overflow with tubes over the side of the tank flows 1000gph with a 2 inch difference between the water in the front and the back of the overflow.

If you need the water to come in the top of your sump I would use a stand pipe that is open at the top and let the water come out the side into the sump. No air trapped. Make sure the stand pipe is the same height of the water in the tank plus a bit.

I have 4 x 1.5 inch drains that come into the tub with the skimmer in it.

Fourstars · Dec 15, 2019

Thanks WVned, as long as I’m below the tanks overflow and I don’t create an air lock by directing the flow down again I should be fine? I see you also have a refugium in your system too. Do you think if I direct all flow through the refugium first I’d be okay? I would only have Chaetomorpha which seems to like higher flow, plus I have two HOB skimmers I’d Also run on the refugium. Trying to avoid the expense of a new skimmer. Then I would have it drain to a sump on the floor.