Bruce,
With all due respect are you really sure they really grow that well at 54 degrees? That's well below their optimum range. Just because they seem to be feeding well does not mean they are growing fast. I've seen this feeding trout through the ice. They feed like gangbusters but they are not growing much in that cold of water if at all.
That said your system, knowledge, and ingenuity is impressive. You're giving me ideas.
