I’m treating with Formic Pro which requires removal of entrance reducers but I noticed robbing today. What do I do?
According to the instructions, entrance reducers must be removed to allow for ventilation during treatment. I'm doing the 20 day treatment, so after 10 days I swapped out a strip in each hive with a fresh one which is supposed to be there for another 10 days. This was yesterday.
Today I noticed there were bees fighting at the entrances of both hives and bees hovering around the top covers. I check the hives every day and have never seen robbing until now. I didn't have entrance reducers on before the treatment either. I quickly put entrance reducers in both hives as it seemed the robbing was the more imminent threat.
I can order robbing screens online but that will take at least a few days to arrive. In the meantime, which is the lesser of two evils? Leaving the entrance reducers on to protect from robbing but prevent ventilation of the formic acid? Or removing the entrance reducers to provide ventilation but allowing them to be robbed?
Is there anything else I should do?