As a person gets in to the heavier feeding rates (with higher potential to cause nutrient load probelms in the pond) and higher desired growth rates of the fish, the better quality higher cost feed makes sense to me.
John, this actually isn't true. Feeds improved for conversion efficiency have high amounts of Nitrogen and phosphorus which are both essential for fish growth (the building of flesh and bones). High quality feed does not reduce the amount on nutrients going into the pond. The increased rations of these two nutrients are the reason why. Furthermore, the low CN ratio of high protein waste decays more slowly and is more likely to become incorporated in the sediment to accumulate. To whatever extent this happens, the nutrients are then more bioavailable to Macrophytes than to phytoplankton.
