how many times a hour should the water go through the sump?

[StirCrazy]

Ok this is totaly silly, a 1X turn over for tank volume will have absolutly nothing to do with skimmer preformance. you telling me if I have a 180 gal tank with a 1X turn over a berlin will do a 100% skim on it..

you not going to get a 100% skim unless you match the flow of the sump to the flow of the skimmer, that means your overflows go into your skimmer then to the sump and there is no way you could aford a skimme that will handle that flow.

so in the real world, shoot for between 3 to 10X turnover depending on what the sump can handle. this is the most important thing as depending on how you designed the sump will dictate the max amount of flow that is reasonable throug it. personaly I go for 10 to 20X through the sump as I have it set up like a setteling pond. with 160X turn over in a main tank not much settles out of the water colume so I take it to the sump where it goes high speed through a couple baffeles then just opens up to a very large area where it slows down and junk falls out. so that was about 1800 gal per hour through the sump, my skimmer was a becket fed by a mak4 so irt was probably doing about 800gph.

this 100% vs 10% thing is a waist of a good argument also as no one is going to do a 100% waterchang every month and it just doesn't matter after the say 10 hours of doing 80% and 10% you are gettting the same results from either method and no skimmer has a 100% efficiency, maybe 20% if you are lucky.

so don't worry about skimmer preformance vs sump flow. set it up so the flow is good and not to turbulant in the sump, get the best skimmer you can afford and enjoy the tank.

Steve