AquaClear filter flow rate

[Anna94]

Is it true that if I reduce the flow rate on my AquaClear filter it will filter more efficiently and the water in the filter chamber (50% of it) will be processed multiple times, causing more impurities to be filtered out? That's pretty much what it says on the box.

 

[Potluck]

Okay i don't know what is going on but you just had a post about media, I'd this a bran new filter, if so do Not remove the old one, run them both together until the a new one gets established, and no that is false, I have 2 on my 55 gal tank, one aquaclear 110 and one aquaclear 70, saying that is like saying don't clean a gunked up filter, im looking at my box and no where does mine say that, I run 14.5 turnover rate

 

[Fresh2o]

Is it true that if I reduce the flow rate on my AquaClear filter it will filter more efficiently and the water in the filter chamber (50% of it) will be processed multiple times, causing more impurities to be filtered out? That's pretty much what it says on the box.

In theory, it sounds correct. I think there's more to it.
First off, the impeller will be pushing close to the same amount of water whether the intake it fully engaged or slid to the side. Flow through the media is NOT reduced, however, input and output are. Water not drawn in from the intake will come from the filter box via the slots in the cage. So yes, some water will be drawn through the filter multiple times. Question is, will particles that pass through the filter media the first time be trapped on the second or third pass? Same applied to the dissolved wastes. Will multiple passes of the same water lead to increased processing of nitrogenous wastes? Hard to say without thorough testing.
In a perfect world, the water leaving the filter will be "super filtered". That means minimal particulate matter and waste converted to nitrates. However, that would be countered by the decreased throughput.
Good question. I don't have a clear answer for you. I leave my full throttle for the flow it produces for the tank.