55” x 19” x 19” begins!

[Josh24]

Mark,

QUOTE:
For the CL intake could have it lower to help move the water a bit more. Also the flow seems very low.

Thats what I thought but thats what the calculator kicked out! The pump will be located 6' below the tank but Im suprised the the GPH is that low.

QUOTE:
I've got a Dart and had the impression they are a hi volume but low head pump. Good for CL, but not return, might want to recheck the curves.
http://www.mdminc.com/Dart.htm 50g isn't that big of a sump, specially considering it won't be filled to the top, sure you would want that much flow anyway through it?

I checked the link provided and the return pump is listed at 2000 GPH with 10 ft. of head. Should I be concerned about the sump only being 50 gallons considering the main tank is only about 86 gallons? What would be the downside to having that much flow through the sump?

[mark]

The RC calculator might have a short coming handling a CL with multiple outlets and I think I see what you did. Entering 3/4" for pipe size, calculator restricts the pump outlet to 3/4" where as more likely you'll come of 1.5" then go to a manifold to split.

I looked at the curve also and for 10' head get 1200gph. Take a look at a pressure pump something like an Iwaki RLT series from the reefs.org.

The sump size in itself isn't a problem just having a really high flow could lead to microbubbles and having the lower flow helps detritus settle.

My system is similiar to what you're planning. I have a 145g/75g sump, Dart on CL, inlet 2", connected through a OM 4way going to 4-1" outlets. I'm feeding my basement sump through 2-2" drains (conventional overflows with Dursos) and returning with an Iwaki 70RLT and 1". Off the Iwaki probably getting 1000gph and pump runs a little over 2amp. My thoughts for flow was to rely on the CL for circulation, the flow to the sump really is only to feed the skimmer, heaters and some mechanical filtration.

[Joe Reefer]

My thoughts for flow was to rely on the CL for circulation, the flow to the sump really is only to feed the skimmer, heaters and some mechanical filtration.

I second that. Flow through sumps should be kept to a minimum so you don't end up with a micro bubble problems later. That being said you may be able to reduce the size of your overflow pipe. I can't find it now but there was a thread on RC of a similar tank to what your planning.

[LostMind]

Are you planning on drilling the bottom of your tank? I've seen at least 1 tank break due to that. Just a heads up.

[Josh24]

Thanks for the responses.

Mark:
My caculations using the RC Head Calculator show 2100 GPH but I see you point. I should look to try and get 1000 GPH from my sump return pump and possibly 3000 GPH through the CL. The question then is how do I determine whether I get 3000 GPH through the CL when the calculator dosn't take into consideration the things you mentioned in your post.

When calculating the head loss on the CL I added 6 ft. as the pump will located just below the main floor to reduce sound. Should I not have done this?

Lost Mind:
My plans are to order a custom aquarium complete with holes in the rear panel of glass. No holes in the bottom. Thanks for the heads up though.

[Josh24]

What do you think of using these pumps:

Closed Loop:
Sequence 4000SEQ19 / 4000 GPH at 0 head & 3000 GPH at 10 ft of head.
That should be plenty for 4 - 3/4" outlets.
The question is, is a 2" outlet enought to feed it?

Sump Return:
Velocity T4 / S4 1446 GPH at 0 head & 1000 GPH at 10 ft of head.
This should work well for a basement sump?