Is 3000 gph overflow capability good enough?

[sugartooth]

I ordered the tank (10 ft.x4 ft.x30") with two overflows.
I asked that each overflow have the ability for 3000 gph each.
Should I ask for more?
I'm wondering if I need to increase it in case I want to use some of that draining power for additional close loop?

I already have 2 x 2" drains in the back for closed loop. The output will be 8 x 1" returns for the closed loop.

I'm thinking if I have to add more flow later on down the line, I can go up and over the top of the tank, using the overflow capacity to drive it.

Should I do this a different way?

 

[Elliott]

the purpose of overflow is to skim the surface for organics binding to the air/water interface, feeding your sump. the flow through the sump should be rather slow to allow export of these waste products, about 3-5 x display volume. using overflow for a cl would allow waste products to bypass the sump and re enter the display, better to use a bulkhead well below the surface.

 

[sugartooth]

That's a good point Elliott. Thank you very much. I will have to see if I can place another large hole somewhere.

I just didn't want the tank integrity to be compromised with so many holes.

Thanks again!

 

[Elliott]

np, good luck!

 

[steve the plumb]

I have the dart on a 4 way in an 8 ft tank.I have the drum with the 2 holes(one opposing each other)I have all 1" lines but some of my returns are split in the tank.I do find that because half of the flow is being split(between 2 outlets) when it comes to my split out lets and my single out lets the split one don't get enough flow.(out of my 8 outlets 6 have tee's 2 are not split)Since your tank is 10 feet I would go with a stronger pump plus don't tee off the returns unless you go with an OM that has 1 hole.If you are not going to use an 8 way and you are not going to control the flow you will not have enough flow going to all 8 outlets.I would go with either 2 darts and 2 om 4 way or the 8 way with the stronger pump.Something like the hammerhead should give you a nice flow.I should have gotten a stronger pump or not split my outlets.

 

[gotoneon]

Another thing to think about is noise. The more water you have flowing out of your overflow the more of a waterfall noise you will get. It is always better to increase your water flow with a closed loop system as you can control it so much better. Drilling holes in your tank for closed loops will do nothing to the structure if placed properly. Just keep them away from edges.

 

[sugartooth]

Thanks for the tips. I didn't think about noise either.

I have 2 closed loops planned, and thought I could max out the overflow capacity in case I needed to use it as the tank matures.

How do you get such high turnover in your large tanks? As far as I can see, I can only get 25X turnover with 3 closed loops added.

I wanted to aim for 60X capacity. Without extra pumps actually in the tank I don't think I can achieve this....am I correct?

 

[gotoneon]

That is some serious water movement. I know this is a big tank but that is serious. in my 300 cube i had my amp master 4700 running off two 2" out flows and returning through two 1 1/2" returns. The returns were located 8" below the water line and they still pulled a cyclone down. I had to split each return inside the tank to keep things under control. It was quite funny though, watching the tangs try to battle the current, they love playing in it. With that being said, when I was picking up my 600 gallon tank from the builder he was finishing off a tank that was 6' long, 3' wide and 30" tall. The tank had three 3" out holes and six 2" returns. The plan was for three Sequence 7,400 gph high head pressure pumps. This water flow would be about what your goal is for this size tank. I never saw this tank in action, never heard the noise those pumps put out, and never saw the power bill. Just think, you would have to double that. I know you reef guys like flow, but wow.

 

[steve the plumb]

You can get the stockman pipes or make it its very quiet that or the dorso.