I'm chomping at the bit to get a start on the growing season, but I'm sure we are going to see more extreme cold. I am using DWC beds outdoors. I have some brassicas growing now, albet slowly.
Before I jump in and experiment, I'd like to work off other's experience.
What I thought I would try is to use plastic domes over the plants. On cold days it would keep in warmth, at least enough to avoid frost damage. On warm days, the cooler water temps underneath would prevent the plants from burning up.
That is my intuitive thinking at least, My question is: Has anybody tried this? I was thinking of starting with herbs.
Can't much tell about the plant growing portion of your swimming pool set up from the one pic you have posted...but you might be better off making little polyethylene domes around your plant grow beds. That way you can vent them during the warm days...and get some well needed freah air circulating through there once in a while. And it's easier than dealing with a zillion little individual plant domes.
It doesn't have to be anything fancy (bent pvc pipe and plastic GH sheeting. Kind of how dirt farmers use row covers or low tunnels.