Pond Boss Forums AERATION Systems questions Pond filter for 1/4 acre pond?

This touches on an issue I have been thinking about for a while. If the water replacement rate (or the differential nutrient content of inflow and outflow water) is insufficient to keep the bathtub at some equilibrium, it seems that the only other recourse is to actually intentionally harvest nutrients from the pond. Even when you just clear out vegetation, unless you move that debris out of the watershed, its nutrient content will eventually return to the pond through surface or ground water leaching or suspended transport. Even a filtering pre-pond has the issue that unless you periodically remove waste organic matter, those interrupted nutrients will eventually get back into the pond.

The primary way of removing nutrients that interests me is to harvest high on the food chain (fish) and have a small garden to use the fish remains to grow edible crops. I guess you could compost any harvested aquatic plants to provide nutrients for a food garden.

The problem I have is quantifying the likely net nutrient input. It is relatively easy to find the nutrient content of fish that are harvested. But identifying the primary input sources (I think in my case forested surface water runoff and leaf liter) seems to be largely guesswork.

For reference I have a new (2 yr) 1/4 acre pond in a forested rural area near the Cuyahoga National Park in NE Ohio, constructed from a natural bog (no dam) in a headwater area.