Hello everyone, I have a question I was hoping that the more seasoned aquarist could help me with. I have a 90g tank with a 20 gallon sump. Originally my sump sat under the tank with a
mag 12 running the return. My tank has a built in overflow durso design hand drilled. I moved a few years ago and now my sump is in the basement, I have atleast 10ft of head running the water back uphill. I used to get a real good flow out of the return line, not so much anymore. I currently have 2 Koralia #3's, and two Hagen 70's in the tank now for flow, I plan to remove the Hagens and get one additional Koralia #3. So my real question is would anyone suggest I run a larger return pump? I do have plans here in the very near future to upgrade my sump to a 40-50 sump/fuge design. What would be a recommended turn over rate through my sump/fuge? I have been looking at the Panworld 100px, and the Gen-X PCX-40 (Mak4). Both seem to have some pretty good numbers with high head pressures. Any suggestions are greatly appreciated. Oh btw my return line is 3/4 inch

Have you calculated your headloss flow that you're getting now?

Here's (http://www.reefcentral.com/calc/hlc2.php) a great calculator for figuring that out.

In my experience, and from what I've read from seasoned aquarists, such as Eric Borneman, you don't need to produce all the flow for your tank through your sump/return flow. In fact, if the water isn't gushing in and out, your skimmer will actually have more time to work on the water that is making it to the sump.
I think it's good that you're rather trying to increase the flow *within* your tank. This is not only more effective, but also, in your case, probably a bit more energy efficient.

Tru that, The Mag 12 at 10ft is running 600gph, upwards to 12ft we are at about 450. And I never even thought about the effect having the water moving slowly will have on the skimmer perfomance great info man :) Much thanks. Well it seems like a win win to keep what I have then, I can save money and not buy another pump, not need to drill another tank when I get my new sump/fuge, and I can save electricity by not using a huge a** pump.

i agree with Christi. IMHO, the slower the flow through the sump the better. it gives the skimmer more time to work and if your refugium is in the sump ... it gives the macro algae more time to consume the phosphates.