This time of year it is better to get that thing out of the system so that it doesn't spawn with the Nates. I usually bonk all of the hatchery fish and give them away or smoke them if the meet doesn't look good.

As for knowing when to keep or release a dark fish, your guess is as good as anyone elses. I have caught chrome bright hens that had soft, white, crappy meat and dark bucks that were perfect.