In fairness Brandon, the fish you caught was a blackmouth that had a little pink in it and is known as a "blush". If that same fish had the opportunity to have another summer of feeding on crustaceans (shrimp & krill) his flesh could have possible turned a deeper pink or red up and definitely would have tasted better.
True white kings lack the ability to retain carotenoid pigments, namely astaxanthin which provide most salmon their characteristic flesh coloration.
Salmonids cannot synthesize astaxanthin; therefore it must be present in their diet. As previously stated in this thread, crustaceans have a high concentration of the pigment astaxanthin and the more shrimp and krill a salmonid eats, the redder his flesh will become... unless he is a "white". Think of them as salmon "albinos" and you're on the right track.
Oh, and as for the Tuna Tyrant not liking white kings??? I'll take yours Tobeck... They are nothing short of spectacular coming our of the smoker!!!