I can't tell you all how much I appreciate your input. The lake is a natural lake and has probably been around over 100 years so there is unfortunately no economically feasible way to reduce the size. I'm thinking aeration and no fertilization may be the right approach unless someone thinks otherwise. The overall biomass will not be a problem since we can't catch enough anyway at this point. It is not uncommon for three of us to fish for three hours and bring in around 90 LMBs in the 12 - 14" category. We do not provide supplemental feeding, and the algae I described is filamentous - the green slimy kind. The carp help but can't keep up with the rapid growth. Maybe the aeration will produce a greater area for insects/terrestrials to survive that provide food that didn't exist with fertilization. Any thoughts? Thanks