Thank you Watermom.

Obviously, I wasn't doing as well as I thought.

Next question -- What do I do about the "swamp water" smell? Water is still very clear, but when stirred as in brushing the pool or actually in it, any agitation of it brings up that odor.

Markedly less growth of the algae overnight, and through this morning, so MAYBE (but I doubt) I'm at least pulling even with it, if not gaining a little ground here.

And yet another question:

Can algae spores live through a winter, dried out? I ask this to check a theory of mine. We didn't clean the ladder or any of the rest of the equipment before using it this year, so I'm thinking that is where this stuff hibernated, just waiting for us to give it a new home.