Interesting point. I have no double brood experience, so haven’t seen this effect. There are so many diehards that say you must use doubles, but it seems to be just repeating a long held belief rather than through test and measure.

Good point, Stuart. I’ve always used screened bottom boards, but most commercial operators use solids. It would be a shame if they only depended on synthetic chemicals like other countries did initially. It won’t take long for resistance to develop.