I also am looking for submersable pumps. I have a 45G in the works, with a closed l;oop manifold style return, but the return is coming from the 15g Sump. I was thinking of a Mag 1800,but would that be to much flow through the sump? I was only thinking tank turnover, not realizing how much is flowing through the sump. My setup is not set in stone yet. I do have space I can hide a submersable in my Overflow chamber. The main reason I went closed loop manifold style is I do not want powerheads visible and sticking to the glass.

Thanks for all the responses folks! I've made up my mind and will go with the 1250. Sounds like an Eheim is worth the extra bucks! :)

I have the 1260 and I love it. It was an upgrade from my previous mag 9.5.
I never had any problems with the mag mind you, but it was a little louder than the eheim.

10x or more turn over means inside the display tank for internal flow.
For example i have a lot of flow for sps corals(6000 g/hr + wave box 5000g/hr on 60 gal tank)
3xhr turn is good for return from your sump to main display.
Personally i think slow return rate from the sump is better it provides more time for skimmer to process the water before it will go back to main tank
HTH

Ive got a 1262 and have been very satisfied with it. Its WAY more than I needed - I probably could have used a 1250 instead...

What size tank and sump do you have Ron?

90 Gal tank w/27 gal tank for sump.

The overflow and plumbing will keep up with it at full output but it will generate a lot of microbubbles. IMO using relatively large return pumps in order to get increased tank turnover requires good sump baffle design.

Bud, make sure and give us an update once you have that pump up and running!

Through some "technical math equation" the "perfect" turnover is 6.1x for a reef. This will pass 99.9% of the tank water through your sump every 24 hours. I have ~7x turnover on my reef (the closest to 6.1 I could get). Many people with FO or FOWLR like 10x turnover, but it is really considered a waste of electricity.