Jimmy,

The most accurate way is to sort them during spawning time. The males will expel milt with some pressure wuhile the females will be either really distend with eggs, or if they have recently passed the eggs their bellies will be as flat as a quarter. But even if a fish is distened it is imperative you check for milt. You can also check fish with a capillary tube carefully pushed into the uro genital opening during spawning, but if you don't know what you are doing you can damage the fish.

My supplier raises them in an RAS (Recirculating Aquaculture System)and he hand checked each one out of a tank after he netted them. I don't believe there were any mistakes as I have seen eggs deposited in the pond, but none were fertilized that I know of and I have not seen an perch fry.

If pigs could fly bacon would be harder to come by and there would be a lot of damaged trees.