This is a helpful discussion and I will look forward to hearing the results from Sue and Amanda's test lake. I will be especially interested in your challenge of the industry standard of 1 lake volume turnover per day vs 1/2 turn vs every other day, etc. to maintain appropriate DO levels. Also appreciated the distinction between destratification and DO levels at depths below 12'. Bill C alluded to that distinction in an earlier post when he suggested that maintaining a 2 - 3 degree variance (or closer) between bottom and top temperatures would be moving in the right direction in establishing good DO levels at depth...but not a replacement for actual DO readings.
My diffuser (a single cluster of four 9" diffusers) sits at 22', almost in the center of my generally rectangular lake which is just shy of 1 acre. The system's capacity is 7800 gpm, so if I'm figuring right, if I average a 12 foot depth (max depth 24'), the system should turn the lake over approximately every 8 hours. In theory, I should be turning the lake over 1 1/2 times in a twelve hour period, spread out over three 4 hour aeration periods, coinciding with the hottest part of the day (12 p.m. - 4 p.m.) and two night time segments (8 p.m. - midnight...4 a.m. - 8 a.m.) which includes that period a few hours before and after sunrise where I understand DO levels tend to be lowest.
One caveat for me is that this is a new lake, built in September 2010, so I do not have the sediment buildup of older lakes that would probably require more aeration. I understand from discussions on this board that as the lake ages, aeration demands will increase to keep up with fish and plant sediment, so my results might not apply to many situations.
