@kfigerm, cheers, I was only thinking about the h2o2 this morning. I bought a bottle of 3% a few years ago and used it sporadically I didn't really think it would last, but after 18 months I gave it the potato test and it was active, so I bought a 5L bottle of 12% and put a small splash in every nute bucket I mix up. Does it make any difference? I am not sure but extra O2 cannot be bad.
I can say after enough batches with the new panels that while it probably does not have any effect on growth, it does have secondary effects, it slows down surface evaporation as you say, and absolutely stops all algae, instantly and these corrugated plastic boards are light and do not bend, they stay nice and flat. This makes it much much easier to water if the plug has got a bit over dry. I did find the algae extremely annoying even if it did not harm the plant, because it would mess up my nutes. Also taking them outside to scrub them down was a pain in the ass. Without any equivocation the panels are a must have.
I didn't really have time to prepare my current plugs, I just soaked them in plain water and put in the beans, and didn't give it anything except water for a couple of weeks, didn't seem to do any harm at all! I got a big pile of the large pyramids at a bargain basement price so I'm working through them and building up my used ones.
Regarding air pruning what I have noticed is that there will be white roots that stay healthy on the outside of the plug, but even so by about week five they've gone brown and died off anyway. When I have cut the plugs open, apart from the main roots it looks like there's hardly any roots, so I am guessing that they are pruning themselves very fine. My Mulberry F3 is like 4 weeks and 3 days and is 33 inches tall, so that tells me it's not the plug that is the limiting factor. It has grown 10in in the last 3 days!

The plug in a tub has been an interesting experiment. It does not use up the water in the bottom even if I only leave a small amount. It does not appear to have any effect on growth, but I'm going to put a night owl in one when this tub is done. The point for me was not to make the plants grow better, I'm not convinced that it makes a difference, but just to be able to leave them in place without having to lift them up to my watering table. I'm going to have to make some adjustments to the next tub, but I will wait till I can do an autopsy on this one which will be in a few days, taking down Mondo Smash and Creamix early has been a big success, I didn't lose any weight and the quality of the weed is phenomenal. So while I would normally let this Tre Lime Sorbetto go another week at least, I'm taking her down tomorrow, I'm a convert to an earlier rather than later chop now.
FWIW if anyone is interested I have simplified my nute mixing I just used Micro Grow Bloom, in a 1:1:1 ratio all the way through from seedling to a couple of weeks into flower, then I up the bloom.