I'm with you Tracy, I have never achieved a thermocline in my 1/4 acre pond with the air running. I have lost faith that it can be achieved in a small BOW, AND still maintain good turn-overs. My three diffusers are 3 feet off the bottom and spread out evenly in the dam side half of the pond. I could move them higher in the water column, but then the lift rate diminishes and my run-times would need to approach 24 hours a day. Maybe this would be better, but I don't think so, hence not putting in the effort to raise the diffusers (again).
Going by what Mr. Lusk said, would it be reasonable to conclude, that if you're meeting the bare minimum DO for the species you have without aeration, that aeration isn't required? By not aerating, you're keeping favorable temperatures, which are apparently what fish prefer over water that has more DO than they need.
Some interesting stuff here.
This is were the thread title comes from..."To Aerate OR Not to Aerate". In my case, I am hoping to maximize my little puddle and that is why I have air in it. That and I like to tinker. I believe that aeration should help do that, but the trick in warmer climates is to balance it with the water temps. The one piece of info that I am really missing is...what constitutes dangerous DO levels? I assume that I am pushing that limit, but I really don't know. Bob says "They really can't judge the difference between 3.5 ppm or 6.5 ppm." in this thread...
https://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=522102#Post522102This make s me think that 3.5 ppm is not so bad, but I don't want to take it out if it's original context.
IMO, a pond without air will balance itself. Meaning that once the biomass meets the available DO levels fish will start to suffer in one way or another. This suffering can be in the form of lack of growth, increased illness, or, during an extreme event, a fish kill. An aerated pond allows for more biomass (given that it is done properly and adds DO to the pond), but when the hot summer starts to push the temp limits the aeration must be cut back. This improves the chances of that extreme event. IMO.
EDIT: Added yesterday's data...........................................................................................................
I grabbed some more readings yesterday to compare to the earlier weeks data...
6/2 (5pm)...________Surface (@6")____24" down______36" down
DO______ 6.2____________3.5____________2.3
PH______ 8.1____________7.8____________7.7
Temp_____82 F___________71____________69
6/3 (5pm)...Secchi = 11"
________Surface (@6")____24" down______36" down
DO______ 6.0____________5.0____________2.6
PH______ 8.0____________7.8____________7.7
Temp_____82 F___________75____________70.1
6/4 (5pm)...Secchi = 10"
________Surface (@6")____24" down______36" down
DO______ 6.8____________3.5____________2.5
PH______ 8.2____________7.9____________7.8
Temp_____84 F___________73____________71.1
6/5 (5pm)...Secchi = 10"
________Surface (@6")____24" down______36" down
DO______ 7.3____________4.1____________3.1
PH______ 8.5____________8.0____________7.7
Temp_____84 F___________73____________71.5_____At the very bottom = 70.7
Secchi = 10"
We had 2" of rain yesterday morning and received a good inflow (and out). In the past, the rain water inflow had DO levels at 7ppm. The air run-time was increased the night before by an hour or so. It's hard to tell what the exact reason for the slightly increased DO is, but I think increasing the run-times is helping so I will continue until the water temps get high.
125 crawdads have been removed this last week with and additional 15 about a month ago. I'm looking for improved water clarity. Yesterdays rains did not make it worse, so that's good.
