IMHO, it was the fact that these fish were acclimated to this exact size and brand of feed early in life. NEDOC acquired the feed from the grower that I got the perch from originally, so I think there is some imprinting on that taste and consistency. This may have some implications to other Pond Bossers who are selecting feed for their ponds. If they got there fish from a particular hatchery or grower it might be beneficial to find out what type of feed they were raised on.
I also think the smaller size was important, but we checked the ingredients and I'm under the impression that fish meal was a primary protein delivering component in the feed that the YP like, while soy product was the protein component in the feed they didn't like.
Regardless, it was impressive how quickly and agressively the yellow perch switched to the new feed. They seemed to "remember" it very quickly.
