The bees have become increasingly more productive over the last weeks. They continue to build comb, rear brood, and gather honey and pollen, but they also have started using propolis, a thick glue-like substance, to water-proof the hive and bind the parts of the hive together.
Since I am using baggie feeders on top of my inner cover, they can reach the intersections of the top cover and adhere the top cover to the rest of the hive, which makes adding feed to the hive quite difficult. I basically resorted to removing everything above the inner cover.
The Solution: Add another inner cover. I decided for the screened inner cover because it allows for increased ventilation and does not add another top entrance.
The picture shows the inside of the hive with the screened inner cover in place. You can see the inner cover with the baggie feeders on top. The bees enter the main hive bodies through the center circle.