I tried it, went to a lot of trouble to build two nice big feeders, both hlding about 5-10 gallons. Put some floats in with lots of small slits to enable the bees to keep their foothold and drink without taking a swim, got the idea from some great info on some posts here. Set it up, looked fantastic. Built a special roof to keep the rain out. Came back a day later, very busy and lots of busy happy bees - I am now a master beekeeper! Came back a few days later - huge amounts of dead bees in both feeders. The sheer volume of bees on the floats had weighed them down until some bees got stuck and drowned. As more bees piled on and the weight built, the floats sank further. Catastrophe. Massive losses and I learnt my lesson. I'm strictly an internal hive feeder now, though I MAY try a chicken feeder one day if I get brave enough. Bot not for a very long time.
Cheers,
John.