how many GPH for return pump - NEW question please read post #39

How many GPH return pump would I need on a 29 gallon sump to a 65 gallon DT? This is for a submersible pump.

 

I would think 300-500 gph would be a good turnover.

 

I'm no expert, but go larger than you want, you can always put a ball valve in to throttle down your flow. Just make sure you take in consideration of head height and all that fun stuff. The more bends, the more flow you'll need.

 

Whats the head pressure height going to be?

 

What's your overflow's rating?
What will you be keeping?

 

ok, I need help. Does the overflow need a pump as well? Height pressure? I'm not sure how to calculate that. Should I be even attempting a sump?

My stand is going to be 32 inches high and the new tank is 24 inches high, does that help?

 

I'm going to be keeping my current stock in my 54 gallon and transferring to the 65 gallon. Live rock, softies, several fish, about an inch to inch and a half of sand bed. I would like to maybe try keeping some easy SPS down the road when my flow is improved.

 

The head is the vertical distance between the maximum water level in the display tank and the operating water level in the sump. 4 feet is often a safe assumption as it also includes a bit for line losses due to fittings and friction.
So you need a pump that will do 3 to 5 times your display volume at 4 feet of head. All return pumps have a pump curve or published chart that shows how much they will produce at a given head height. In your case you would want a pump capable of 65x3 to 65x5 or say 200 to 350 GPH at 4' head.

But before you size the pump you need to know how much your overflow box is capable of draining back to the sump so you do not outrun the overflow. Common sizes are like 300 GPH, 600 GPH etc and you would want a overflow box that is capable of more than your pump can produce for safety.

Here is what I think is the best simple explaination of sumps and oveflows on the net, Marc has done a great job of describing them and even includes a working model. He als oshows you how to DIY sumps.
http://www.melevsreef.com/allmysumps.html

 

thank you for the link! I've tried reading information but I get very confused on the articles I've read. I will check this one out!

 

Well I must be over doing it. I have a 30G tank with a 10G sump and the return pump is 396GPH. No bends in the return or the overflow. But I have like inch and a half line for the overflow.... It works well and I've never had a flow issue.