study on skimmer performance

[ScubaSteve]

Originally Posted by MarkoD

So a skimmer with better pump that creates finer bubbles is better? But what about the footprint and height of the skimmer? Would that create a huge difference?

Does it it make a difference? It does, yes. But that's what I mean by "bigger" skimmer. The effectiveness of a skimmer is determined not only by the size and quantity of bubbles produced in the skimmer but also by the residence time of water in the skimmer.

The longer a particular parcel of water spends in contact with the bubble phase, the more organics are attached to the bubbles (thus increasing removal). The more bubble surface area, the more removal. The greater the separation of organic-laden bubbles from the water, the reduced chance of re-entrainment (thus increased removal). All of these have an effect on the skimmer performance. The "removal rate" that they present in the paper is an aggregate rate that takes into all of these effects.

And it IS possible to calculate the theoretical removal rate of the skimmer and how it changes with all of the different design parameters (maybe this will be something that I'll teach). But the number one parameter that will have the greatest effect is the skimmer volume. The bigger the volume, the bigger the throughput and the greater the residence time. A tiny skimmer with a huge pump that makes tons of bubbles isn't going to do much because the water won't stay in the skimmer long enough for it to matter (and you'll just fill your sump with bubbles).