July 2019 Introduction: I’ve removed the video that I originally uploaded with this post because I don’t think it’s a good idea anymore. Screen stapled over the middle of the hive top feeder, for me, is the way to go now. I also staple screen inside the reservoirs on the bottom to prevent the bees from getting into the reservoirs when they’re empty. See Screened Hive Top Feeder for more details.

Hive top feeder with screen in the middle so the bees are contained inside the hive. (Oct. 10, 2016.)
I have no love for hive top feeders. They can be heavy and messy and a farcical tragedy when things go wrong. But this simple and cheap modification virtually transforms them into kill-free feeders and, at least in my experience, makes them easier to use. It also allows me to put various rims over the feeder, or anything I want over the feeder, without risk of drowning any bees. Obsessive-compulsive mad scientist beekeepers (a significant portion of the beekeeping demographic) could easily build on this design so that the feeder virtually refills itself. I can already imagine how that could work, but I digress.
Do have a feeder to fit a Flow Hive 14×20â€
I don’t. I can’t say I’m a fan of the Flow Hive either. Good luck.