My friend was thinking that these hives would eventually get clogged with Propolis. Has that ever happened to anyone?
All my hives have propolis filling the cracks but that does not impede anything to do with the hive. Also, almost no one owns a Flow yet (they are still in production) so almost certainly have not had this experience with this hive … so turning to FAQs on this site:
"Apart from the trough at the bottom, you don’t need to clean Flow™ Frames unless you detect disease in them. You will need experienced beekeepers to give you advice on disease prevention and response for your area.
The plug for the honey collection trough is designed with tiny grooves that allow a bee lick up any residue honey that collects behind the plug. Sometimes the bees block these grooves with propolis (a resin bees use to plug any holes in the hive) but it is easy to clean this out by removing the plug. We haven’t experienced propolis build-up in the frames themselves."