Closed loop and return pump Q's

[cpreefguy]

Hi, I just bought the 58 gallon from R.Allard and it is drilled calfo style. The left calfo hole has an overflow and is being used for the sump but the right one looks like it wasnt used and has no overflow. There are 1" bulkheads on each hole, which return pump should I get for the sump? I would like enough flow for SPS.
Also, I wanted to put another overflow in and run a small closed loop or something but have no idea on how to plumb it.
Any suggestions?

[cpreefguy]

nobody?

[GaryP]

Something like a Mag 5 should be plenty for that sized tank. Its going to depend on how much flow your overflow can handle.

Gary

[matt]

When you say "drilled calfo style" what do you mean exactly? Does it have several holes in the upper part of the back wall of the tank, and a calfo overflow shelf attached? If so, you're lucky; that's a great set up.

Regarding the return pump for a 58, I have to disagree with Gary; a mag 5 is not an appropriate pump for this IMO. I'd go with a pan world or iwaki external, at least 750 gph. Then, you'd want to supplement with a closed loop or some other internal tank circulation.

[GaryP]

Matt,

I thought about that but I think the 58 is a hex or pent. I was afraid that much current would be to much for a tank with that small of a horizontal cross section. I may be wrong. Also, my thought was a smaller pump on the return and more on the closed loop. Since I don't have a lot of experience with closed loops I was going to let someone answer that part of his question.

My theory was less flow on the return and more on the closed loop where you aren't fighting a head pressure penalty.

What is the geometry of the tank?

Gary

[cpreefguy]

36x18x21
I was thinking a mag 5 or 7 for the sump and the same for the closed loop. I hadnt thought of an external pump.

[GaryP]

There are some big advantages to an external pump. The only real disadvantage is cost. Keep an eye out for a used one here. Most closed loops I have seen have used an external pump. I'm not sure how you would use a submersible for a closed loop. I guess it could be done but it probably wouldn't be very practical. I am by no means a closed loop expert.

Remember that a Mag 5 pumping from a sump is only going to give you about 350-400 gph of flow. That's fince since you are only looking to get enough water there to feed your skimmer and whatever other equipment you have in the sump. You canmake up for that flow with your closed loop. If there is very little loss of pressure at your closed loop pump you would get something around 450 gph. Your going to lose some do to friction and other mechanical issues. That's a total of 800 gph. That means you would be turning over your tank about 10-12 times per hour.

I've been using a Via Aqua that is rated for about 1300 gph in my 75 and I have been very happy with it. I don't have a closed loop in there. I supplement it some with a couple of Maxijet 1200s. The main reason I have the maxijets in there is to provide some turbulent flow. The Via Aqua by itself gives a lot of flow, but it just makes a big loop around the tank.

Another thing to consider when sizing a pump is that you won't always get the same flow from it as you did when it came out of the box. The flow rate will decrease with age and also between times that you clean it. I try to break mine down and clean out the impellors every couple of months. Its better to do it routinely than to wait until it seizes and burns out the motor. I had plenty of experience with that early on with Rio's. They are notorious for it, among other things.

Gary

[longhorn_20m]

I also have a 58 RR, and I'm in the process of doing the plumbing too and was tryign to get ideas. When you say use both holes as overflow, does each have its own standpipe, or do you mold them into one? That was an idea I had, and route new return over the backside and t off to each side. I guess my question, what is the flow rate of using just the overflow? and then with using both holes?

[cpreefguy]

Here is a pic so you can get a better idea.
http://img1.imagevenue.com/loc274/fa1_100_1689.JPG

The sump is a small Dan's wetdry and I think one line to it is sufficient, should I drill it and run an external pump on it also?

[longhorn_20m]

No, it has teh single overflow in the middle with a hole for drain and return.

[cpreefguy]

there are 2 1" bulkheads, one is just covered by the overflow.

[cpreefguy]

Oh, I was told that it was calfo, I have no idea what a calfo shelf is.
Here is a pic of the back:
http://img3.imagevenue.com/loc298/cfe_100_1699.JPG

[matt]

Yeah, that's not anything like a calfo. Anyhow, that looks like a very small overflow box, so I have to retract my recommendation for a bigger return pump, but I'd still go external; stay away from mag IMO. Lots of people wil disagree, but I've had bad luck with them. Go for the pan world or iwaki that pumps 500gph or so, and use the other hole for your closed loop. Just hang the return lines over the tank edge.

[cpreefguy]

That sounds like a good idea.
Thanks

[NaCl_H2O]

I think Matt's response summed it up well. If you can go external, the PanWorld pumps are very good.

Important note: PW pumps (or Iwaki) perform as advertised (head loss). My experience with MAGs is that their performance drops off MUCH more than advertised with a few feed of head pressure so you need to buy a step or two above the rated GPH.

If you have to (or prefer) to go submersible for the sump pump, Eheim makes the best one IMO.