Bobbss,
It wasn't clear if the question was directed to a pond with fish or a hatchery. But Sunil's observation is common. The difference between a 4" fish and a 2" fish is substantial ... the 4" fish is more than 8 times as heavy. In a hatchery, 2" fish could be maintained in a crowded condition with little growth by feeding only maintenance rations of feed (~0.75% of body weight daily). No one likes to see fish maintained this way for such a length of time (4 months) especially predator fish that are hoped to be trophies some day ... ergo ... the troubling thoughts. Eric brings up a valid point about the possibility of a latter crop ... so maybe that explains it.
