Just wondering how high off the bottom the air disk should be set off the bottom of the pond? I did have it set at about 10"s and over time each year the weight sinks into the clay bottom till the disk is only and inch or two off the mud bottom.

I am going to extend the disk 2 feet up from where it is currently. Wondering if this will be enough to help keep the clay particles from mixing when the air is on?

Cheers Don.

I just installed my aeration yesterday. Max depth of 10.5 feet. Diffuser is set on to of a platform of milk crates (4 on the bottom, 1 centered on top) that puts the diffuser 22 inches off the bottom.

I'm in the break in stages right now, but at that depth, other than at initial startup, I don't see any distribution of bottom particles in the surface water.

Don't know if this helps, but it seems that elevation from the bottom isn't disturbing the bottom very much.

I'm confused. I thought you would want the diffuser very close to the bottom so that the anerobic bottom muck would be exposed and thus begin to degrade. I know I read that somewhere....lol

Definitely two schools of thought on this. Some say put it on the bottom, some say elevate to maintain a small level of stratification and cooler bottom water.

While I'm sure having the diffuser on the bottom will definitely stir up more silt, with time I think that decaying matter will still be handled. Just takes longer.

As long as water can circulate downward to the bottom, O2 is still being introduced, maybe not as heavily as a bottom set, but it still gets down there.

I don't have a plate on my diffusers. They're mounted directly to the top crate, so water should be pulled up from below/thru the platform. It's just not causing a major disturbance of the bottom. I still see a little silt, but only on initial start-up then it clears up.

I should also mention, my diffusers aren't the disk type, their rubber membrane tubes, so there is minimal interference with current.

Our pond is heavy clay, I mean our township was well known for making clay bricks and field tiles.

This clay as it get super saturated with water turns into a jello that is about 10-16"s deep. My weight and air disk are at most 10"s tall. After pulling up the station the other day to clean the disk I found that the weight was full of super fine clay and the disk was sitting about 1"s from the pond bottom.

From the beginning of time with the aeration we have had a visibility of about 18"s max. The other day I pulled water from the pond and let sit in a bucket and fine clay settled out.

My thoughts are that as much boil we see at the surface there should be that much in draw from the bottom. I have these two stations in question in the two deepest parts of the pond. I would like to cut down on the suspended clay so if I need to fertilize the plankton I know its not clay changing my visibility.

I am thinking of 24"s more than what we are at now and see if it makes a noticeable change.

Cheers Don.

My pond is similar as it it basically one big clay bowl. It took about 6-8 months to clear up after digging. I plan to add aeration next year but still haven't decided exactly where or how deep to place the diffusers, so please let us know if raising your disk makes a big difference in water clarity. I imagine it probably will.
Thanks

From what I have read, mostly here at PB...

1.) Diffusers at the bottom maximize the aerobic decaying process.

2.) Diffusers at the bottom maximize a consistent temperature from top to bottom while potentially reducing the surface temps to the greatest extent (given that one does not over-aerate and super heat the pond).

3.) Diffusers off the bottom minimize turbidity issues by not stirring up clay and/or silt.

4.) Diffusers off the bottom are believed to leave somewhat of a thermocline for heat relief for the fish.

It's my deduction that those in cooler climates are less likely to need that lower thermocline for heat relief and bottom placement makes a lot of sense unless you have clay that will stir up and suspend while the warm climate pondmeisters should try and maintain that lower thermocline and sacrifice the benefits of a full aerobic atmosphere all the way to the bottom. Those in between the warm and cool climates need to experiment a bit more and may even have to move some diffusers around at different season if they wish to maximize the benefits of aeration.

I live in Missouri and my experiment, thus far, is working out fine.

I have a 10 foot deep 1/4 acre pond with 3 diffusers. One is placed towards the middle at 7 foot deep while the other two are near the edge at 4 and 5 foot deep. All the diffusers are on stands that put them 20 inches off the bottom. I believe my pond is turning over entirely as the temp at 7 foot deep is only one degree warmer than at 10 foot deep. I do not have that lower thermocline that I was shooting for, but I don't think I need it as the lower temps are typically in the low to mid 70's. It would appear that I have found a sweet spot, quite by accident, that does not increase turbidity, but turns the pond over entirely.

My 2 cents.