Keeping fish alive has alot to do with your boat. Personally I beleive 15min is too long. When my Triton is set on "Auto" it kicks on every 3 min for a period of 1 min. It pulls lake water in while allowing lake water to run out. I also have a 500gph pump.

I have never added ice to the livewell. Alot of times it does more harm than good. Escpecially what you dont see after a tournament. If you catch a fish in 90d water temp, then place it in 80d livewell water, yes it does fine. However when you release it back you are throwing it in 90d water and sometimes the fish goes in shock and does not recover.

In the summer when I catch a fish livewell goes to auto. Anytime the boat is on pad it goes to recirculate. Treatment, "keep alive" is added around every 2 hours. I keep the water a blueish green tent.