Thanks for asking. This is what I have been doing. I posted a photo above of a coho trough that I use for coho and medium size chinook. Notice the scissors in the rod holder spot with the pliers. I stun the fish with a few light taps (thinking the heart is still pumping by not hammering them), lay it upside down in the trough, and take the heavy duty kitchen scissors and cut through the complete stack of gills on both sides…..completely sever them. The initial bleed out is massive (into the self draining engine well) but I follow up with a few five gallon bucket drops over the head which forces the gills open and further bleeds the fish out. I wait at least five minutes before placing the fish in the cooler and flush a few more times beforehand, and even after a day of full retention with a few guests, the cooler hardly has a trace of red.
One more step is to take a hand brush and brush off all the sea lice, and flush again. No garbage in the cooler.
If you ever trolled on a commercial boat, “second grading” is to be avoided, so “care of the catch” is imperative, and I try to carry that forward.
I zoomed in on the scissors, fish is upside down at gill cutting time though:
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