I don't have a DO or temp meter. I don't think it would tell much this year since I had full depth aeration until a few days ago. The real test will be next year.

My basis for doing it was the loss of rainbow trout 2 years in a row. Unfortunately trout seen to sink when they die and I didn't realize what happened until this year.

My pond is a rounded square shape with one corner being the deepest at 15'. Most of the pond drops off to 6-8' quickly and stays there. I want to add a regular bottom diffuser in 6-8' of water kitty corner to this one to try and keep the other side from stagnating.

If I can create a small cold area with oxygen for 4-5 trout I will consider this successful.

I will say if I was to do it again I would do it differently. I would get a 6" plastic concrete footing bell from Lowe's or hd and attach it to 6" pvc going vertical. Level to slightly below the surface I would put in a tee with a leg to the side and add some extra up pipe to keep the water from going out over the top. From the tee I would go over another 2' and do another tee again with the two ends pointing towards the sky and bottom. Short up pipe again to let bubbles out and keep water in. Then 6" pipe down towards bottom to release water, with a tee at the bottom to send the water horizontally. A float would keep the surface cross tube half out of the water. It would be an air lift up then across and into the down pipe. Probably $250 -$300 for materials for the piping, float, and anchoring system.

It would be much simpler than the behemoth I created.

For my creation I plan on putting a cap on the pvc with a few holes in it to reduce the water being pumped up.