Question about Overflows

[Pole04]

So that thread title is about as ambiguous as it could be, but I couldn't really find a way to sum up this question quickly. This will be my first reef tank and I am wanting to get things right.

So the setup I am planning has my large display tank on a steel stand above a sump (pretty standard). I am planning to feed a display refugium using part of the overflow valved off from the display before it ever hits the sump.

This display refugium will sit level with the sump in the bottom of the stand. There is no room to elevate it any. The refugium will have its own overflow that I planned to run back to the reactor section of my sump. I have not drilled the refugium yet or installed the overflow I ordered, so if there is another way I need to setup, I can change course now.

My problem is this. In my understanding, I won't have the assistance of gravity to take the water from the overflow of the refugium back to sump. I thought of using a small pump (I want low flow in the fuge) to push water back, but I don't know how I could really dial in the difference of water coming from the DT to water being pushed to the sump. This also sounds like it would be inviting disaster when the small pump failed the fuge would overflow.

I need help! Space is at a premium but I will do what I can to accommodate any changes I need to make. Any suggestions are greatly appreciated, and if you would like any more information just ask. Thanks!

 

[Reefer1978]

Could you explain a little more why you can't elevate it at all? All you probably need is 2 inches. Maybe post a picture?

You could drill both sump and fudge, at the same identical level (high) and then put in bulkheads and connect with pipe. It would do the trick, but doesn't sound ideal to me.

 

[Reefer1978]

I would also feed the refugium with water from the sump, not right out of the display, after it passes mechanical filtration. You are not going to have a lot of flow in the fudge, and unless you have at least one pass through mechanical you will have settling in there.

 

[Pole04]

Sadly I am just in the very beginning of putting this all together. The fuge is outside being leak tested and the stand and tank were just moved into place Tuesday. I will try to explain the best I can and failing that I will get some pictures and drawings tonight. If all I need is 2" of fall it might be possible.

The sump is 15"tall, I am using 1" PVC for the fuge return so the height would be at 16ish" high. I would REALLY prefer not to have drill the sump if it isn't necessary. It is an acrylic BashSea sump and one of the best looking pieces of my setup.

The refugium is 21" (with top trim) tall 24"x 24" wide. The overflow I bought from Melev's Reef is a horizontal floating overflow (12" x 4" x 5") that will be attached to the top middle of one side of the fuge. I need space to mount a light above the fuge, and I am hoping to make the light easily movable so I can get in and work in the fuge when necessary. There is a possibility I could raise the fuge an inch or two, but any more and I risk not being able to work in the tank comfortably.

The stand has 29 1/2" of vertical clearance.

So if I am understanding right, and I mount the overflow just below the top trim of the fuge at about 20.5" I could drill the fuge at 18.5" or so and have a 2" drop from the fuge to the sump and that should be enough to keep the water moving?

 

[Pole04]

I had originally planned on feeding the fuge from the sump, but along the way I kept seeing people T off from their overflow lines to feed the fuge, so I figured that would be standard. I think I have an extra pump I could use to do that. Would I want to feed it from before or after the skimmer?

 

[Reefer1978]

More then enough space bud, you are good. In mine, I have it cut 1" form the top, and there's plenty of drop. So 2" will be great.

Personally I like my fudge clean. So I Tee'd mine off from the return line with a gate valve, so I can control the flow. So it's past filter sock, and past skimmer.

 

[Pole04]

Hey I really appreciate the input! I am finishing up the drawings of my plumbing tonight and hoping to order everything then. I will make the necessary changes, and I like the idea of T-ing off the return. I had planned on a manifold, so I could actually just add a T on that and be done with it. It will make the overflow plumbing much easier anyhow. I think I will use a gate valve on that portion the manifold so I can really control the flow.