View Full Version : Sump Flow Question

Pete H.
06/22/2012, 01:19 PM
I have a 130 gallon tank that I am looking to plumb in. I have 2 corner overflows. Each overflow has room for a 1 inch ABS bulkhead and a 3/4 in ABS bulkhead. I was planning on running each 1 inch bulkhead as the drain. Use one 3/4 as the emergency overflow and use the other 3/4 as the return.

I plan on connecting both of the drains together and placing 2 tees where I can drain to a fuge and the second sump. I plan to put ball valves into the lines to control the flow to the fuge and the sump. Then the emergency line would go into the fuge for sake of ease of plumbing (Unless anyone has a main concern with that) Then my pump would be in the return chamber. It is a viaaqua 2600. There will be about 5ish ft of pressure head to overcome with the pump. I think that means I will have about ~400 GPH flow back into the tank. Here in lies the main question.

QUESTION: How much flow needs to go through the sump?

I have heard 2 things:

1. You need a minimum of 8-10x tank volume to go through your sump to keep the tank oxygenated. (Won't need many powerheads then.)

2. You want a slower flow through your sump. (2-3x water volume) This is better for your skimmer and fuge to take out the bad nutrience. However, you will want at least 10x water volume flow in the tank via powerheads to keep the tank oxygenated. (Recommends leaving tank open.)

Can someone with some expertise help explain this to me. I am trying to decide if I need to look into getting another powerhead.



06/22/2012, 01:44 PM
I just built a new sump and did something a little different than what is normally done. I have a mag 24 for my 150g and it is the only pump/ powerhead. The skimmer and filter sock go in the first chamber of my 40g sump. My fuge is built along the back wall and the pump return chamber is a "L" shape around the fuge.

It allows me to have a bypass around the fuge so the flow isn't too fast through it and I can still have high flow through the sump. I made the distance between the bubble trap baffles extra wide so I can put a bag of carbon in it when needed.

Pete H.
06/22/2012, 01:47 PM
I am hoping to do something similar. You will see in the picture that I have 2 overflow in. I want to regulate down the fuge so that it has slow flow. Then the second inlet is by the skimmer. That will be faster. I will just regulate it to match the pump. I am just trying to find out if I need a bigger pump or not.

06/22/2012, 01:53 PM
We have about the same size tank. After head loss I'm returning 1,700gph through two 3/4" eductors. If you're only returning 400gph I think you're too low.

Pete H.
06/22/2012, 02:11 PM
What type of pump do you use then?

06/22/2012, 02:38 PM
you are a little confused!

sump flow rate is generally 4 to 10 x tank volume, or matching it to your skimmer;

tank flow rate is 20 to 60 x tank volume depending on coral needs!

example: i have a 300 gallon tank, i run about 3000 gph through the sump and 2 powerhead at about 10000 gph, that is 13000 gph or 45 x tank volume.

also your skimmer should not bypass your bubble trap!!!