Suggestions on a return pump for a 75 gal?

[Trex420]

Hey all. I'm going to hit you all up again for you experiences on a matter. I'm setting up a 75 gal. I figure that I have 4 feet of height from return pump to return nozzle. There will be no turns in return line except for the U shaped return nozzle hanging over the tank's back. I'm using an Amiracle Maxi-Reef 400 for a refugium, this is fairly large 36"x12"x14", I believe it can handle a good amount of flow through it. Space under the tank is an issue. I have 48" to work with and the 36" fuge has a bulkhead built in. I plan on running an external pump to cut down on heat in the tank. I had thought about a Mag 12 but then noticed that a Mag 18 is only $15 more! I plan on placing a ball valve on the output of the return pump to restrict flow if ever necessary. After 4' of head loss the GPH is 1390 on a Mag 18 and 1100 GPH on a Mag 12. Any thoughts people?

Tom

 

[tomu]

what kind of overflow do you have? If it is just a sing tube that hangs on the back, it will not be able to handle that much flow. IMO a good flow rate is 10X. That would give you a mag 9.5 about. If you put something like a SCWD on the pump then you could get a larger one. What are your plans for the return, and what kind of overflow do you have?

 

[vypr2002]

imo I would build a loop that has multiple outlets and run a sequence dart on it. that way you get lots of turbulence in the tank. and the extra outlets will eat up alot of the flow to help match it with the small overflow.
if you can drill the overflow out to a larger pipe and add a couple u-tubes to the thing to pull more water.

 

[larryl]

I've seen a lot of people recommend lower flow rates through your sump, more like 3x to 5x of the display volume. IMO you might be better off using a smaller return pump there (e.g. Mag 5 or 7) and using the Mag 12/18 as part of a closed loop to get the flow higher in the display tank where it can do more good. Running higher flow through the sump doesn't necessarily improve skimming capability (the water just rushes right by), and can create more problems with microbubbles.


Larry

 

[rkl303]

I agree with larry. Go with lower flow for return lines and more overall flow with close loops or a tunze inside the tank.

 

[PSEUDOREEFER]

Mag pumps are not the best externally as well. They advertise external ability, but the seals can't really handle it. If you're willing to run them submersed a mag pump would work great. I ran a 75 on a submerged mag 12 with great results, but a CL would have been better

 

[larryl]

Mag pumps are not the best externally as well. They advertise external ability, but the seals can't really handle it.

Depends who you talk to. I've run Mag 12s external for six years at a stretch with no trouble. I think the trick is to make sure your plumbing isn't putting any torque on the faceplate, and be *really* careful about not stripping the screw holes if you ever need to open and close it back up. I like them because they're relatively cheap and reliable, there are probably better options w.r.t. running external if you want to spend a little more money, e.g. Ehiem 1250.


Larry

 

[PSEUDOREEFER]

wow maybe I'm just cursed :lol: I've tried running a mag 12, 5, 7, and 2 externally and all of them leaked :mad2: BTW I remember them being advertised as being able to be used externally, but I just checked on marinedepot again and there's a note near the top that says they are not recommended for external use Did they change the seals recently or something?

 

[roguemonk]

I've used a Rio 2500 and Rio 1700 successfully with my 110 G. It is not overpowering and you need to supplement with a closed loop. I had a bigger pump for a while and I found that the extra flow was not worth the extra trouble. I don't have a closed loop on my current tank but I plan to use them in my future tanks to replace the ugly powerheads.

I wouldn't restrict the flow on the output of the pump with a ball valve. I always build a branch off the main line with a ball valve so I can divert some of the flow without stressing the pump. But all the flow has to go somewhere, so typically that would be back into the sump/'fuge itself, and this can also aggravate bubble problems and overpower the sump if it can't handle the whole flow from the pump.

Good luck!

Brad

 

[Trex420]

I have two 600 GPH overflows and plan on using 1" hose for both overflow lines as this usually gives a fairly staight shot to the sump and avoids any serious bends. I would like to use the flow from the return to help with water movement in the DT. I don't know about building a closed loop system yet as part of the return but it is possible. If I did put in place a closed loop would I then be able to handle 1200+ GPH return, I know it wouldn't truly be a closed loop as the water is coming from the sump/ fuge area. I was thinking of using several heads that are able to be pointed in different directions. I would most likely use 1"-1.5" hose and the same for all the fittings in the return system, that is another reason I am skeptical of using a SCWD, the reduction involved in going from 1.5" tubing to 0.5" for the SCWD then back to 1.5" after the SCWD. Would a SCWD handle the flow of a 1200+ GPH pump?

 

[Clown-N-Around]

If your overflows can only remove water from the tank at 1200 GPH, then you cannot add water faster than 1200 GPH or your tank will overflow. There is no need to buy anything more than 1200 GPH for your sump pump. If you must use a bigger pump, then I would go with Roguemonk's suggestion and divert some of the flow back to the sump (the pump must output 1300 GPH, for example, so 100 GPH would go back to the sump and 1200 to the tank. The pump must receive 1300 GPH, so 1200 from the overflows and 100 through the sump from the pump itself). There is really no benefit to doing this as it only increases turbulance in your sump, it is just a work-around so your tank doesn't overflow and your pump doesn't cavitate.

Therefore, I would stick with 750-1200 GPH for your sump.

However, this only gives you 10-16 times turnover. Depending on what corals you will want to keep, you need more flow. 20-40X turnover. That means you need approximately 1000-2000 GPH more flow than your sump/overflows can handle. This can be accomplished by pump(s) where the water goes directly into the pump and back out without a sump or anything in between. This/these pump(s) can either be submersed directly in the tank or outside the tank as a "closed loop". A closed loop is the same principle as a submersed power head, you just use some pipes to get the water to the pump and back throughout the tank.

For referrence: On my 125, I use a Mag 9.5 (run externally with no problems for me) for my sump and a Sequence Barracuda for my closed loop. I have a CPR/weir overflow that runs up to 1200 GPH for my sump and 1 1/2" plumbing for my closed loop with two submersed "swiss cheese" (holes drilled all over) tubes to feed my sequence pump. There are three pictures of my closed loop in my gallery with descriptions.

Hope that helps!

 

[jonthefb]

On my 65 gallon with built in overflows i have a mag 12 and mag 9.5 both plumbed off the fuge and externally and have no problems at all

What type of animals are you planning on keeping in the tank as the types of fish corals is going to directly depend on the amount of flow you have through the aquarium.

good luck
jon

 

[Trex420]

Brad is this what you mean?

Clown-N-Around

I think with head loss included the output on a Mag 18 would be less than 1200 gph but just barely. I haven't found a chart for a Mag 18. I'll still go with a 1200 gph just to be sure. I'll have to rethink the brand a little as I'm getting mixed feedback on running Mags extrenally.

I plan on having LPS, softies and trying some SPS. The fish I have currently will stay with the 29 Gal, except for the Pyxie Spotted Hawkfish, it is a bully. I'll frag a lot of the softies I have in my 29 and move my Hammer, Torch, Candy and Frogspawn to the 75. The t-5s I just installed in my hood are awesome even with 17 month old bulbs. I can't wait to see corals in the new tank.

 

[jdallred]

Here is a chart to the Mag Pumps

If you are looking for the best most efficient set up then you have some great advise above from people who have already been where you are. A lower flow through your fuge is going to be more efficient and better for the system. If you are worried about flow then I would consider a "true"closed loop (not run from your fuge/sump). If cost is an issue with doing both (which for most of us it is) I would do some research, decide on what you want, and then try to find the pump(s) used (either local or on RC's selling forum).

If you are looking for an alternative to the Mags I would look at either Iwaki or Gen-X pumps. Check out the link to Marine Depot below.
http://www.marinedepot.com/aquarium_pumps__index.asp?CartId=

 

[larryl]

Brad is this what you mean?

That's close to what I have set up, I'd suggest a few small changes:

1) Put the straight part of the tee so it runs vertical from the top of the pump outlet, so that you have a straight shot up from the pump to the tank return. This will help minimize losses in the flow back to the tank, where you want most of the flow going. Then the short side opening of the tee points horizontally to the left toward the sump return.

2) Add another ball valve in the vertical return, above the tee. If you open the valve to the sump and close the valve to the return, this will let you divert all the flow away from the tank (e.g. for feeding or maintentance) without shutting off the pump. Also, it will give you the ability to throttle back the pump output - especially if you use a Mag pump, because they tend to be noisier if running full open, and much quieter if running against some back pressure.

3) Consider using union ball valves instead of regular ball valves, so you can shut both valves and remove the pump for service or replacement. (Make sure the unions are between the valves and the pump!)



Larry

 

[roguemonk]

Yes, that was roughly what I meant and I agree with all of Larry's suggestions.

Brad

 

[Trex420]

I also agree with Larry's advice. The image I used was only a rough draft to express the concept. One thing Larry is T-connectors are SOC fittings and most other parts used are threaded. I'm assuming you glued some fittings. Correct? Below is a picture of my return for my 29 gal. I haven't seen union ball valves around so I did something similar but with no return to sump.

 

[larryl]

One thing Larry is T-connectors are SOC fittings and most other parts used are threaded. I'm assuming you glued some fittings.[/B]

Yeah, I plumbed mine all PVC back to the tank, so I have a threaded-to-slip adapter at the pump outlet (with teflon tape), and a mixture of glued slip fittings and threaded fittings the rest of the way up.

I haven't seen union ball valves around so I did something similar but with no return to sump.[/B]

I actually have a union fitting next to each ball valve, like you do. I just suggested the true union valves because a) sometimes you can find them cheaper than a separate valve and union would cost, and because they take up less linear space if you're working in a tight area.


Larry