JP, I can say that I took out over 1500 crawdads last year. They probably averaged 4" long and the single trap was in the pond, on average, 4 days a week between late April and the end of October. The trap bait (fish pellets) was changed in the evening and not checked again until the next evening (24 hour soaks). The secchi visibility stayed between 10 and 16 inches all last year. It showed no signs of getting better as the season progressed as it just jumped back and forth with the blooms and rain inflows. The pond blooms can be very heavy (very heavy) and certainly affects the visibility. It has been about 14-16" so far this year with no aeration turned on and one bloom already that has disappeared, mostly due to spring rain inflows and muddier waters. As far as vegetation goes, the pickerel weed, arrow head, & thalia dealbata all thrived and spread out slowly, but nicely last year. All other submerged vegetation is non-existent. FA only grows in the top few inches of the water column and has not matted and floated around since the first two years of the pond (about the time the craw population explosion). The overhanging grasses, hanging lily baskets, shoreline rocks, and the dock floats all have FA on them, but it is only at the surface. DO levels have always been low in my opinion. I did not take many DO readings last year, but they mirrored the previous year when sampled...4 to 6ppm (Better at the surface and diminishes as you get deeper).
Unfortunately for the pond hobby, I am working more than ever and have another hobby (auto restorations) that takes up my time too. Taking a scientific approach to the pond will be a bit hap-hazard at best this year. Maybe you (JP) can (I know you can) make some estimates on the above info should you care to venture some rudimentary conclusions to last years efforts.
