The predator/prey balance is a constant concern for a pond owner who wants a well managed pond. Too many fish in a pond causes water quality problems and Mama Nature always gets even.
Excellent point Dave. Its real easy as a pond meister to have a tendency use adding more fish as a solution to a pond problem. My guess is that many times simply selective culling would be better than adding more biomass. To me it parallels a home aquarium, which probably most of us have had at one time or another. You always want to add a new colorful fish. And then one day you have a tank chock full of fishies and suddenly you have water quality issues. It never occurred to me (dense at times, I'll admit it) that a pond is a huge aquarium but without a forced filtration system and for many of us without aeration and without a 20% water change every week or two. The whole idea of calculating total biomass per volume of water was a revelation to me. (Biology and science were never my best subjects in school, hence the bean counter profession, heck I'd have been a doctor if it wasn't for all that medical stuff).
