Tracy,
Something you could try that might work. If you got a single unit of soil floc (1 bag of part A and 1 bag of part B) and got in a boat and applied a little around each diffuser, maybe a 10-15 foot circle around each one, let it settle and if you had some left you could even go back in a couple of weeks and do a 2nd application.
soilfloc works better in warm-ish water so you could consider trying it now if water temps are warm-ish, or wait till spring warmup.
I have NOT heard others do this before but I'm only going by my experience. The bottom of my pond is a sand/clay mix and when you rub across it with your boat or a stick you get a plume of sand/clay. I never knew if my cloudy water was from my aerator, or crayfish or goldfish stirring up the bottom. I tried raising my aerator on a plastic tote but like you, never really knew if that helped or if it was one of the many other variables.
I know in the past if I had to push a stick into the ground in the pond to tie off a minnow net it just sunk right in with little pressure. Now fastforward and I'm status post 2 separate soilfloc treatments, one a year ago, the other this past Sept. Even after 1 treatment the bottom has become kind of like concrete. I have to twist and twist to get sticks to penetrate and sometimes resort to a hammer. I also pounded in some fence posts to hold up my seine net and the soilfloc laden sand congealed around them to the point that I could not get them out. I ended up bending the bottoms by wiggling the tops back and forth and still couldn't get them out. Later I had to wade in the pond and took a lot of effort to get them out (they were only pounded in about a foot but the soil floc really packs itself around them and doesn't let water get in to loosen up the particles as you wiggle them back and forth)
You can scratch the top of the sand in my shallows now with a trap or a stick and no plume at all. It is like that sand grout where it looks loose on top of the grout but the particles are almost cemented together.
Since you could easily apply soil floc around your diffusers just far enough to stiffen the sediment around the plume zone, it might be enough to eliminate that variable. I really don't know how much a diffuser can be blamed for stirring up water especially if they are up off the bottom by a foot or so.
Just a crazy out of the box thought.
