BOD removals over 90 % through ponds.  Effluent TSS is less than 20 mg/l.

Peter

You could put a variable speed drive  on your floating aerator and then run the aerator only as fast as necessary to maintain a DO of say 1-2mg/l. The variable speed drive will use some power itself but the slower speed of the aerator will save much more if the speed can be reduced substantially.

Odour is obviously one quality measure but it would seem that your BODs are currently pretty good as well.

TerryF

Low DO in the second cell appears to be stratification(turnover). However if the blowers were running at all, this wouldn't be the problem.