Is that just rocks and water in that one? I'm putting out a lot of water containers in this drought. I always have wasps, birds and wild animals that come to them. Other things also. But do the bees need to get water with those rocks or something in a container?

Charleen fixed a sugar syrup mixture in that feeder to keep the bees away from her hummingbird feeder. She used lava rocks to keep them from accidently drowning. She was worried that the tornadoes that hit close to her might have damaged the bees nectar sources for a bit. Jan (Mekos) is planning to set up a plain water one this summer.
The rocks can be gravel, pebbles, marbles plain old garden rocks or whatever. The purpose of the rocks is to give the bees a landing surface which will allow them to collect water without drowning from falling in accidently. This would also help butterflies.

I've heard of people providing containers with sand, rocks and water for butterflies...especially for those butterflies prone to do what they call "pudding". Just hadn't heard about doing it for the bees. If the bees have enough nectar plants available, would they still need such a feeder? With hummingbird feeders, I've mainly had problems with wasps visiting it...not bees, usually. In cool or cold weather, I've seen bees going into soda cans (those I collect a while before turning them in). Soda-flavored honey...I wonder if they have that.

If there's plenty of nectar available the honey bees usually won't touch sugar water. When we set up a new hive from a swarm we provide them with sugar syrup to tide them over until they get things set up to suit them in the hive. Last year we had one hive that seemed to be lazy about gathering their own nectar. All the others set up at the same time were busy bringing in pollen and nectar but that one kept drinking the sugar water. This year we don't have any doing that.
Charleen was worried about the hummingbirds not getting any syrup because the bees covered it. So I told her to try giving them some sugar syrup away from the feeder. She tried a quart jar with a chicken waterer lid on it first and got worried she had drowned them and fixed the one in the picture. She reported yesterday that the bees still go the the hummingbird feeder when they run out in their's but are starting to visit flowers again. Her only problem is with ants and I told her to use cinnamon sprinkled around the base of the stand as they are said to not like cinnamon. Jan told her to also coat the bottom of the stand with Vaseline.

The cinnamon and vaseline are cool tricks to remember against ants for other things too!