I'm thinking of adding a different chiller to my 28 HQI Nanocube. I had a 1/20 Nano Arctica on it at first, but that only lasted a few months before it started acting up, so I took it off and have been using fans to "try" to keep temps down, but the tank would still hit 84f at times. The one thing I did not like was using one of my back chamber return pumps to plumb the chiller. I tried the route the chiller return back to one of the rear outlets, but the water pressure was understandably decreased, I'd like to avoid using one of my return pumps on a new chiller. So, with space being at a premium in the rear chambers, I don't know if I can fit another, 3rd, pump back there for a chiller. Here's a poorly drawn graphic of my idea:



Can an external mag-drive utility pump (or other such external pump of the correct size) be used like this? Are there any issues readily apparent that I'm missing. I know there is a name for the extended tube with screw on cap that is higher than the aquarium (used to fill/prime the external pump) but I don't recall what it is. The quick disconnect, on both the inlet and outlet tubes, would allow for easier, less messy maintenance on the chiller. I hope this makes sense. Thoughts please...

Thats fine. Yes the Mag can be used and would be a better choice then the maxi because of the distance you need to travel plus rate of flow you want. Add a couple of unions and ball valves for maintenance.

I posted a reply on another site but here's a pic of what I did.
The pump has since been replaced with an Eheim 1250 and all flexible tubing is black, as clear has algae problems.

VDub90, thanks for the image, that's awesome, practically exactly what I have in mind!

Well, got my plumbing done today. Waiting on the strainer from Marine Depot before I cut the pipe to go in the back chamber (so I know the length). Decided to put a "T" in the return so I could also feed a GFO reactor.

Wouldn't the Eheim 1250 be too much flow for that chiller?

I have the same chiller with about 4ft of head loss and I was using the MJ1200 and it was just too much flow for it. The chiller is rated for I think 85 gph.

I was originally using a MJ 1200 externally and I was concerned with the heat it put out. I figured it would self distruct itself and cause my tank to cook. You could barely touch it. The next pump I used was a Mag 3 and I dialed it down with the ball valve. The Mag 3 hated it. absolutely any blockage of the flow would cause it to rattle like mad. The Eheim I can turn down to a trickle and the pump doesn't make a sound. You can actually block the flow completely and the pump is still quiet.

I'm pretty sure the rating of the chiller is 85gph minimum. I have also timed it for cooling at different flow rates, and it really made almost no difference. With the Eheim full bore it's about 30 mins, with the gate valve about half closed it's about 27 mins.