Designing a sump...

[Justin L]

After reading tons of articles about sumps, I still don't get how to design one, so excuse my ignorance.

I have the basic concept, so lets put myself into a scenario.
Lets say I'm going to set up a 75 gal FOWLR. The tank is going to come with 1 corner overflow.

So, if the drain is 1" then water is draining at 600 gph right? That would mean I need a pump that can pump equal to or less than 600 gph with lets say a 5 foot head pressure. Therefore a good pump for this would be a Mag Drive 7 because it can pump 420 gph under 5 foot head pressure right?

Also, how far apart would the baffles have to be from each other. I've heard 1", 2", and 3".

If you could, please post some pics of your sumps.

Thanks in advance!

[Reefugee]

Justin,

You got the basic concept. It might be useful if you can give us the dimension of the sump. Also - are you going to be running a refugium? Are you going to do an in sump skimmer? More details might help.

Minh

PS - my baffles are about 1.5" apart. Melev recommends 1".

[WayneL140]

I'm in the same situation. We just got a 75g with single overflow, used, with what looks to be a 20g sump. The lady had a Mag 7 for return and was using, ugh, bio balls. I'm going to baffle the sump and create a refugium, too.

I'll be watching this thread, closely, too. Any help we can get would help a lot.

TIA.

Wayne and Lynn

[kenny77]

go to this site. you will find a lot of option and sizes of sump.

http://www.melevsreef.com/allmysumps.html

[Avi]

If planning a new sump, do yourself a favor like Wayne did, and plan a refugium at the same time so you don't have to hassle when you decide to do it later on after the sump is up and working. Then, you'll be far more limited in what you're doing.

Ideally, you should have three or four sections:

1. for your water pumps, including the sump return pump
2. for the return(s) from your overflow(s)
3. for your refugium.

Some considerations in the ideal setup are that your refugium section should be fed by the return of your skimmer since that is more refined water than you'd get from the returns from the overflow(s). Also, IMO, it's best to incorporate baffles just before the pump section that will accept a strip of sqare foam, the width of the tank long by about two to three inches square, through which the water would have to go...so that any micro-bubbles that your configuration might create would be filtered...before reaching the return pump. Micro-bubbles aren't something that you know one way or the other that you'd have so it's best to prepare for them and make the fix easy in the event that you have them.

[Justin L]

Thanks for the link Kenny.

For the sump I'm thinking about getting a 55 gal and I do want it to have a refugium and I plan to have an in sump skimmer.

Skimmer to Refugium to Return. I do plant to have four baffles with a bubble trap right between the skimmer and refugium.

Okay, if I order an oceanic 75 gal thats reef ready, what is a megaflow? Is that the type thats in the middle? Also, I assume it has a 1" drain and 1" for the return?

On melevsreef.com, it said a 1" drain will drain at a rate of 600 gph. That would mean I would need a pump that can pump equal to or less than 600 gph with a 5 foot head pressure right?(This is a guess on tthe head pressure, I don't have the tank yet)

Again thanks for all of your help.

[Justin L]

Also, whats the difference if the baffles are 1", 2", or 3" apart. More flow the farther apart they are?

[WayneL140]

Another question--(I'm researching, researching, researching, but specifics are tough)--

As I'm going to have to angle the PVC at some point, which should be bent, the drop from the display tank or the return? Does two 90 degree turns hurt the efficiency of the Mag 7?

Good info; good thread. Thanks a lot.

Wayne

[Avi]

A good way to maximize the flow through your sump and tank is to take the maximum your overflow can handle, which in your case from what you're saying is 600 gph and use this:

http://www.reefcentral.com/calc/hlc2.php

Get a pump that's rated at 600 gph PLUS the amount of head loss in your system. Many pumps are marketed with the information already calculated for the consumer, so for instance, they will tell you "600 gph at 4 feet of head." You'd see that, for example, at this page in the "performance curve" for the Quiet One 3000:

http://www.marinedepot.com/aquarium_...n.asp#qone3000

Of course, that's not the only pump that'd give you that capability, but you'd have to look at other specs for other manufacturer's pumps to get that kind of result so you can match up a pump for your needs.

[Justin L]

After using the calculator, then the mag drive 7 would be best for this application correct?

I'm still not sure on the baffles and what the difference is if they are 1, 2, or 3 inches apart?

[TimD]

Does two 90 degree turns hurt the efficiency of the Mag 7?

Use two 45s in the opposite directions to achieve better flow. A 90 is a huge loss. Always in plumbing, better flow comes from straight runs or wide sweeping curves, and the more abrupt the change in direction, the worse your flow drops off.

[Avi]

"head loss" is a combination of all kinds of things like distance that the water has to travel, turns, equipment, etc. It's a combination of all the things in your particular plumbing configuration that slow down the flow from any pump. The Mag 7 at 4 feet of "head" gives you only 480 gph which is less than you might want since you can go up to 600 gph with your overflow. Just going "up" one model from the Mag 7 may not give you the correct flow for 600 gph at your "head." A Mag that's one up fro the Mag 7 may give you too much or too little to be 600 gph. If you want to a pump that gives you exactly the flow that your overflow is capable of, which is 600 gph, no more, no less, you have to figure out what the "head" of your plumbing is. (You can go less but don't ever go more.) Then, once you figure out the "head" you can go about finding the right pump for your needs.

[Justin L]

I get it now, thanks.

[Avi]

Okay...it's just that a pump's rating is for "0" head, so that your system WILL have some head so you have to get a pump that's stronger than one that will do, say, 600 gph at "0" head...HOW MUCH stronger is what you'll have to figure out using the head calculator and then looking at the manufacter's specs and finding a pump that does the 600 AT what your plumbing's head loss has.