Another CYA question

[tiki]

I installed a new 1600 Intex sand filter for my 16X48 Ultra frame yesterday, happy with that so far. I also have an intex SWG. I vacuumed the pool since we seem to have a metal problem and I'm guessing the powdery-ish brown stuff that has shown up on the bottom for a couple of years now is a result. I use Metal Magnet and it works quite well. On to the CYA question:

I had these test results yesterday:

FC-7
CC-.5
PH-7.2
CYA-45
CH-20
TA-70

I know the FC was alittle high so I didn't run the SWG last night. However I did add Conditioner Granules as the Pool Calculator said to add 18 oz.(I used approx 15 oz) I mixed them up super well in warm water as the package said and they mostly dissolved. I don't see and granules anywhere so I tested again this morning. I guess I should really follow direction here and added them with the sock because these are my results today:

FC-3
CC-.5
TA-60
PH-6.6
CYA-80

I am wondering if the CYA level will actually raise in the next week and if it is normal for the addition of the CYA granules to lower the FC, PH and TA by that much? I feel like I really don't know what I am doing even though I keep reading pool school and the posts here in the forum. From what I have read in pool school and the calculator I am shooting for FC-3-5 ppm (depending on CYA), PH 7.5-7.8, TA 60-80, CH 50-300, CYA 70-80 with salt 200-400 above the recommended level from intex. Does this seem correct?

 

[JasonLion]

Adding CYA will lower the PH, and perhaps the TA as well. But it shouldn't have any direct effect on the FC level.

I would expect the CYA to go up a little more, but it might not. CYA takes a while to dissolve and show up on the test, just how long isn't completely predictable. We say a week not because it always takes a week, but because it never takes longer than a week. Sometimes it is faster, hopefully in this case it was.

You need to raise your PH a little, but otherwise you seem to be doing fairly well.

 

[tiki]

Thank you so much Jason. I think I have OCD when it comes to the test results