I opened the hives the other day and did a small inspection, first hive lots of bees, pollen sacs loaded, seems to be very happy…Second hive had 4 frames that had 0 activity on them and mouldy dead bees ( about 12 of them ) there seemed to be lots of liquid in these 4 frames but I had left them with a top feeder full of 1:1 sugar water 7 days before that. , and the other 6 frames seemed active. I scraped out lots of dead bees from both hives and a good load of frass on the bottom boards. has anyone had mouldy fuzzy bees before? could this be winter condensation?