Well, the PO came through and delivered my temporary filter plug today. Yay! The OEM part is due May 14-15, but this dubiously-rated third-party plug will work in the meantime. Installation was a breeze, pump fired up and the filter filled right quick. I'm back in business!! I only lost a day of operations, and I used that day to exchange water, so it all worked out. To be honest, had I not been down yesterday I would have found some excuse to do the exchange some other day. Now... it's all done, along with the filter cleaning. Good to have all that behind me.
I tested the water, and my FC, like
@Newdude's, was in single digits. But I tested at FC 1 (ONE)! Yikes. No doubt due to recent high temps, low CYA and a missed day of SWG operation. So I've got liquid chlorine going in. And CYA going in, targeting 60 for now, so I don't overshoot. I'll test in a few days and adjust.
I actually did a full suite of tests today. My TA was whacked, at 130, but I think that's to be expected, as I pumped about 2K of high-TA city water into my pool yesterday. The water softener strips the CH, but not the TA. I'll give that a few days, too, before I panic.
But the great news: my CH is now at 440, which is just a tad under my target 450 for the water exchange I did. Success!! I'll record all my new data points for next year.
Now I'm working on my dang auto-fill valve, because it's been flakey lately. I'll report back if my MacGyvering works.
PS. I looked around for a 1.5" M-MIP to 3/4" F-NPT last night, to add a valve to my filter drain. Nada. I wonder if such a thing even exists...