The thing is, the rust all settled out. The pool looked awful, but only because the rust sediment on the bottom made it look that way. Moving the hose around blew the rust away, so I went and got the cheapo pool vacuum and tried vacuuming it. That did not work, because the rust particles are too small to be filtered by the vacuum's bag. That's not a problem, though, because once the pool is full and I can start the pump I'm going to shock it and add flocculent; and then after it's circulated for a few hours, shut the pump off overnight, then try vacuuming in the morning and see how we do.
After my efforts, half of the pool looks crystal clear and the other half looks horrible, because half the pool has rust on the bottom and half does not.
But then I noticed that the float ring had gone flat again. Not as flat as it was when I found it, but decidedly not fully inflated, so I wearily got a spray bottle with soapy water and started to hose down the float. My first lap around the outside didn't reveal anything...until I pumped the ring back up. As I was doing that, I saw a nice big bubble growing on the opposite side of the pool. That, I figured, was my leak.
I found not one, not two, not three, but four punctures, and a few sharp indentations near them. One was V-shaped, with a triangular flap, and the span of the V was perhaps a millimeter across at most. The next-largest one was maybe a quarter of that diameter and didn't really show that it was leaking until I'd patched the first one; I found it by inspection rather than bubbles. The other two punctures did not show as leaking until I patched the first two, but they then had little fizzies going on with the soapy water.
I'd taken an entire 2" square of patch with me, and I used all of it.
My first thought, upon seeing the plug out, had been "sabotage", but then I realized that there are not any people around here I'd suspect of being so pusillanimous as to do something like that. More likely that since it was hotter yesterday than it was Thursday night, the thing had just popped loose.
But seeing the tightly-grouped punctures makes me think something was chewing on it. Possum? Raccoon? It wasn't a rodent, since they use their incisors almost exclusively; if these were tooth marks, they were made by carnivore/omnivore/scavenger teeth. So, not a rabbit or a squirrel.
Why on earth a critter like that would chew on a vinyl pool is beyond me. Maybe a baby raccoon? It's not like it would taste all that great, but baby racoons are curious creatures and they'll try anything you toss at them.
Anyway, I got the holes patched, and now I'm waiting to see if it goes flat again. I don't expect it to. I do expect the pool will be filled before too much longer, though.
* * *
Anyway it feels cooler today than it did yesterday. I'm not sure why that is, but I sure did get hot and sweaty enough working in the sun, even though all I was doing was applying patches to the pool. *sigh*