Want to build a closed loop

[steveoutlaw]

I currently have 2 1" overflows and a mag9.5 running through an OM super squirt as a return. I would like to change that to having a mag5 as the return with the outlet somewhere on the back of the tank behind the live rock. I'd then like to make a closed loop with my mag12 running through the OM super squirt. My goal here is to increase flow in the tank while giving my skimmer more time with the water.

 

Are there any problems running the mag12 externally?

 

Should I convert 1 of my overflows to be the intake of the closed loop or should I build one like this:

 

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

 

Any advice or opinions are appreciated.

 

Thanks.

[ErikS]

Hmmm....lower flow through the sump....seems I've heard of that before......

 

I'd go with using one of the overflows for the CL, unless the 1" hole can't keep up with the mag 12 (course you could always enlarge that hole w/ a dremel - seen pics on RC, just never had the stones myself).

 

Using an existing hole sounds like cleaner solution.

[craby]

The only problems I know of running MAG pumps externally are noise, heat, & leaks. When submerged, the water acts as a vibration dampener & heat dissipator & the pump can leak all it wants w/o ill effect. You need to also make sure the hole you use for the C/L supply is low enough that the pump will not draw air as this makes a ton of noise w/ MAG pumps.

[HowardofNOVA]

Steve,

According to the info from Reef Central on Outflow Specs:

1/2" will outflow about 145gph

3/4" will do about 330gph

1" at 590gph

1 1/4" @ 910gph

1 1/2" @ 1325gph

2" @ 2350gph

3" @ 3650gph

 

A MAG12 will inflow about 1200gph, serious problems with not enough water to cover suction.

A MAG9.5 will be about the same, MAG7 would be about right.

Now this is considering on the inflow. Coming out you could use a Ball Valve, but not the story here.

 

According to this readout, I would use a simple "U" piece either DIY 1" PVC with Strainer on one end into your MAG12 then using simple Clear 3/4" Tubing into SCWD split to 2 "U" shaped return pipes for returns.

Ex: www.Ebay.com and go to Bid #7711159325

 

Howard

[dchild]

I run a Mag 7 externally. It is not quiet (though it could be a lot worse). It runs pretty hot - not comfortable to touch for more than one or two seconds. I'm told the heat will greatly decrease pump life (I've only had it running for a month or so).

[steveoutlaw]

Ok, can anybody recommend an external pump that's good, cheap and around 1200 gph? Or does anybody have one they'd like to trade for a mag 12???

[HowardofNOVA]

Steve,

Use the MAG12, will do a fine job. Others will work also, but are rated for both!

Howard

[steveoutlaw]

Howard-

Now I'm worried about the noise and heat issue. I think I'm just going to sell my mag12 and go with an iwaki or a mak.

 

Steve

[stank]

Little Giant pumps are priced low and run forever without worries, just a tad bit on the loud side.

[JC Pollman]

My 2 cents:

 

I have burned up way too many MAGs when run externally - don't do it! And if you do, buy 2 pumps, so when the first one dies, you can replace it immediately and send the other one back to Danner. I really hate waiting 3 weeks for a replacement pump.

 

I have switch all my pumps over to Eheim and Pan World and am very happy. The Eheims, in particular, are really well made: I have a 1050 from 1995 that is still running! I also have redundancy in all my water circulation, so any pump could die and it will not grossly affect the the tank.