I tried the red solution and I have had just as good, if not better, results with the clear water/sugar solution. One cup sugar to 4 cups water works well and much, much cheaper.
On a side note, has anyone had a problem with the hummers fighting over the feeders? I don't mean just the swoop and smack, but actually going for a couple rounds in circles? I've been watching a group of 4 this morning (2 females, 2 males) and they are really aggressive. The females are the ones who are terrorizing each other and not letting the other get to the feeder. It seems as though the male sits in the tree, watches and when he gets tired of seeing the females duke it out, swoops in and tries to break up the fight. However, the females turn on him and he flies back to the tree.
Now, I'm assuming that these are females because they do NOT have the ruby throat like the males. Would this be correct?
And in response to an earlier post, I only had a couple hummingbirds last year and now I have about 4 more this year. I think they will increase as more birds realize you have feeders.