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

[golf nut]

The opening post asked about sump turnover,not tank turnover. whether you like it or not if you have an overflow box you do have a prefilter box they are technically doing the same thing, why are people saying as I said years ago that having no teeth in the oveflow box is more effective? why because it skims better.

[StirCrazy]

Originally Posted by Bloodasp

believe what you want until a thorough study comes out about it. The skimmer isn't the only equipment in your sump .

I just lost all my typing so I will try get it down again

there was a study, that showed that the best turnover was between 5 to 10% with almost as good in the 3-5% range and the 10-15% range.

now this is hard to quantify and a useless study because it is only aplicable to a system with the same size sump, display tank, skimmer and even simular tank stocking as if you change any one of thoes aspects you alter the outcome. so unless we at least know sump size/shape, display tank volume, and the skimmer he is using no one can even pretend to say what sump flow rate would be good.

now as for Mr OM's 100%vs10% thing, pure bunk.. first all no one does constant weekly 100% water changes so it is a fary tale.. Second no skimmer has a 100% efficency so it aint going to happen, your skimmer probably skimms at a 5 to 15% efficiency at best.

but it was a entertaining thread.. made me chuckel a few times.

Steve