TF-100 Kit Arrived Today - I think I'm losing FC nightly

[dakstn]

Thanks to the help here, I believe my pool is all good now. I just wanted to summarize and wrap up my issue.

I started the SLAM process on 5/29 and stopped it yesterday because that was the first morning where my OCLT results were acceptable (FC only dropped by 1.0 ppm). This morning it only dropped by 0.5 ppm.

From 5/29 to 6/3, I added 15 bottles of liquid chlorine (12.5%) to maintain my SLAM level of 20 ppm (my CYA is 50).
I turned off my chlorinator for the duration of the SLAM process.
I ran my filter continuously and it never needed backwashed (pressure remained at 17psi from beginning to end).
I vacuumed once every day and scrubbed the walls for the first 4 days.
I checked the FC and CC levels 3 times per day except for 6/2 and 6/3 when I only checked in the morning and night because things were improving.
I didn't add any liquid chlorine yesterday or today.
Pool was crystal clear the whole time.

My current numbers taken this afternoon using TF-100 kit are:

FC: 9.0
CC: 0.0
TC: 9.0
CH: 450
TA: 220
CYA: 50
pH: 8.0

Going forward, I'll run the OTO tests daily to keep an eye on the pH and chlorine levels and will add my 3" tabs as necessary. Maybe once a week, I'll check all the numbers and occasionally run the OCLT.

Thanks again for your help Richard320

 

[Oly]

Those trichlor tabs are going to raise your CYA pretty quickly and getting above 50ppm CYA will not help your sanitation program unless you intend to install a salt water chlorine generation system. Use liquid bleach to chlorinate.

 

[Richard320]

Going forward, I'll run the OTO tests daily to keep an eye on the pH and chlorine levels and will add my 3" tabs as necessary. Maybe once a week, I'll check all the numbers and occasionally run the OCLT.

Thanks again for your help Richard320

Have you found Effects Of Adding Chemicals down at the bottom of poolmath? It can tell you in advance how may pucks you can use to raise the CYA to SWG levels. Don't forget that they're very acidic, so they should help lower that TA too.