I released the two biggest steelhead I caught, both would have been legal to keep but The thought never occurred to me. One was a hen in the Elk river in Oregon that was 37" long - I didn't know the fish formula then but likely that one was well over twenty as it was huge in girth. The other was a buck on the upper Quinault that I subdued with a fly rod and measured with the cloth tailors tape I now carry, that one was 21 pounds by the formula. Both of those fish gave me the battle of my life and deserved to be let go. And both days I limited on smaller fish after releasing them anyway - good karma from the fish gods I guess