The first couple of days of the conversion, I was adding bleach every few hours. Since then I have gone to adding bleach only in the evenings. Overnight FC loss is getting worse. Is this typical? I don't feel like I'm making any progress. If anyone cares to look at the FC readings and comment, I'd appreciate any ideas. PDF file attached. Am I being impatient?

That is curious. There is often a dip in overnight results when you stop adding chlorine during the day, but it should then start improving from there instead of getting worse. You haven't been testing latter in the morning have you?

Perhaps it is time to get PH and TA test results again, to make sure they haven't wandered too far. It would also be helpful if you could describe what the water looks like.

Have you been doing CC tests? That is another number that gives hints about how things are progressing.

Lately, I have been taking morning readings after sunrise (7:30 this morning) only because the FC drop is substantial and I didn't feel like I was going to be anywhere near 1 or less.

Here are the current readings:

FC - 2.5
CC - 1
TA - 150
pH - 7.5

Water looks pretty good to me. It has been very clear for the past week. Pic is from this morning. I haven't been taking CC readings until today.

Does it make any difference that I've been using "Splash-Less" Clorox? The solution is noticeably thicker.

Would it cause a problem if the several thousand acre corn field my house backs up was just fertilized? My wife says they sprayed some chems recently. She thinks it was Tuesday. This may coincide with the dramatic rise is overnight FC lossess.

I feel like I've been following the conversion directions pretty well but maybe I'm missing something. Thanks for your help.

I would avoid the splash-less bleach. The thickener will eventually build up enough to cause problems in the pool, though it takes a while.

Fertilizer really chews through chlorine. If any is blowing into the pool that could account for everything.

CC is down to 1, which is really good.

Must be the fertilizer or whatever they dumped on the field causing heavy chlorine loss. I'll just keep adding bleach in the evenings to get FC up to 15 and then look for an overnight drop of less than 1 before proceeding to change out the sand right? I'll look for some regular Clorox.

Put in 420 oz at 6:30p to take FC from 0 to 15. Measured at 8:30p and FC had dropped to 5.5 in about 2 hrs! Used the rest of the bleach I had on hand (210 oz) and this should have increased FC by 7.5 per the pool calculator. Need to get more bleach tomorrow. 50 gals total used so far.

Overnight FC drop of 5 is lowest in about a week. Maybe things are turning around. Probably just jinxed myself.

Passed the overnight FC test! Am adding 54 oz of CYA to get it 30 ppm by hanging a sock at the return. CC is currently 0.5. If CC stays low tomorrow, I plan to stop shocking and get to normal water balancing. I think I'm almost there! Water looks good and pH is at 7.2. I've put the ladder in place and assume there's no issue swimming.

Congratulations!