Sizing of nw pumps

[HydroMan]

Has anyone figured out the optimum flow rate of a nw pump based on reaction chamber diameter? I have a 5' tall 4" dia skimmer I'm considering modifying and I'm wondering what size nw pump to get. I'm leaning towards one with a flow of approximately 500-700 gph although I'm not certain how that would work.

Right now I have a venturi skimmer powered by a pressure pump that works but I feel that it isn't living up to it's potential because of the turbulence in the reaction chamber. Unfortunately, I don't remember what kind of flow rate I'm getting through the skimmer so I'll have to remeasure that this week.

[Mr.Marls]

I think you could go even more than that Sedra 9000 maybe.

Or a more cost effective choice.

Octopus-3000

[JCTewks]

you've got to figure the that a lot of pumps aren't going to handle the head pressure of a 5' tall water column...you may be better off with airstones and an air pump for that tall a skimmer.

Jeff

[HydroMan]

I realize that very few pumps can handle more than 3 feet of head pressure and still power a venturi so I would probably have the nw pump inlet towards the bottom and the outlet about 1/3 of the way down from the top of the skimmer.

I've considered a traditional downdraft skimmer but when I've needed air pumps for other aquariums, I've had poor luck finding air pumps that last longer than six months.

I just measured my discharge and I'm pushing approximately 160 gph through my skimmer. It works out to be 2.5x tank volume. I'm looking at the nw pumps people are using on their skimmers and they have over 500 gph running through their skimmer with little to no turbulence. Since I'm getting turbulence and I only have 160 gph running through the skimmer, does that mean it's more an issue of bubble size? Would large bubbles increase turbulence? Maybe I can find a needle valve to put on the air inlet to my skimmer.

[JCTewks]

what is the amount of air mixed with that 160 gph??