Check out this DIY observation hive dome. Easy to make and low cost.
It has the advantage of redirecting any condensation to the side walls of the the bee hive.
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Instructions allow you to build a top feeder and a non feeder version. The big plus of this dome is that we do not get condensation in winter soaking the frames. Instead the condesation is redirected to the sides of the hive. Result happier and healthy bees.
