I have three new hives, they are about one month old. I have all three on screened bottom boards with plastic insert. Well I read many comments from beekeepers and came to the conclusion that the plastic inserts needed to stay in place to prevent to much ventilation. Wrong. Today I pulled one of the sheets and found Wax Moth larva crawling around on them. All three. About 20 larva on each board. Very few mites. Two small beetles, which I assume are SHB. The bees drop much pollen and wax onto the sheets, they cannot get at the sheet to clean it, the Wax Moths find it and here we go. For me no more closed wire mesh bottom boards. If it proves to be to much ventilation then I will replace with solid bottom boards. As a newbie I ask your guidance on this/these problems. Thanks.
Another point I have Bacillus thuringlensis subspecies kurstaki 15 % Can I spray this on an active hive? Or should it be only for spare frames and boxes? At the proper concentration of course. Is there a different subspecies for bees?