Pond Boss Forums AERATION Systems questions How do I only aerate top half of my water column??

I think how deep the Vertex diffuser can pull water will have a lot to do with the temperature profile of the water column. The more divergence of the top and bottom the less distance below the diffuser that it can pull water.

As far as diffuser orientation, I think relates back to a prior comment by esshup. ""Moving the diffuser heads into shallower water might help you by creating more wave action - you'd get more CFM from the compressor...."". When esshup and I were experimenting with this topic for our article in PBoss magazine about winter aeration, I discovered that creating larger bubbles caused more surface wave action. This greater wave action caused the open ice hole to be larger than an upwelling that originated from small bubbles deeper in the water column. I am also guessing this probably caused less deep water circulation. I created larger bubbles by using a single 9" ceramic air stone and also by not having a diffuser or a coarse bubble diffuser on the end of the hose. Experiment with these two ideas and they will give you a better idea of "surface wave action" and deep water mixing.