Finman. Tell me more about the terrarium heater. What wattage is it? Is it temperature adjustable? Do you set it just high enough to keep them in cluster so they don't use stores, or do you crank it up? Just wondering.
I use terrarium heater at spring when brooding starts after cleanin flight. Feefing pollen and heating is very good combination. Last spring I kept heaters from March to end of June. We had really cold start of summer. I had in my all hives heater. I started to use them 2 years ago when I lost 66% my colonies.
15 W terrarium cable is good. 8 W is suitable for nucs. 3 W is meaningles.
15 w is too much for winter.
Also I use now, when I start new little colony with 3-4 frames, queen can lay eggs 3 times more than naturally. Little nucle developes very quickly. After a month hive will fill the whole one box.
I tried last winter heater for 4 little hives. The smallist was 2 frames. It went trouhg the winter. I can say, that without heater 2-frame colony will die normally. Now it was very healthy.
Now my all hive are big, and they are too many.