I am following the 11/14/2008 Nitro sticky How do I use Chlorine in my Spa (or pool)?
Caveat ::: Does CYA dissipate from a water sample over a few hours in an (almost) enclosed container at room temp? I had the ≈ 4 oz water sample taken a few hours before, in a clear 8 oz squirt condiment container, but the tiny squirt cap was not on the spout. Could the CYA have dropped to an unreadable level in these conditions? Am I doing something else incorrectly?
After balancing my 335 gal hot tub's fresh fill to: TA 50 ppm, FC 0, CH 250 ppm, I proceeded with the Dichlor/Chlorine to shoot for an initial FC level of 10 per Nitro's rec. Per the rec. of the PoolMath App, I added .8 oz (wt. via scale) of Dichlor (Spaguard Chlorinating Concentrate Sodium dichloro-s-triazinetrione dihydrate 99%) for initial shock.
.8 oz Dichlor added increased FC to 11.0 ppm (0+11)
1.2 oz Dichlor added over three days increased FC by 14.4 ppm cumulatively (4.4+3+3.6+3.4).
I must be misunderstanding Nitro's post. I thought he was saying each independent time that I raised the FC level by X, that CYA would be created of (.9 x X). Given that, I have increased FC cumulatively by 25.4, so CYA should be at (and should test at) ≈ 22.9 ppm (24.5 x .9). Do I have this wrong?
I filled a 1 oz squirt bottle to 7 ml (140 drops) of the room temp sample water, then added 7 ml[oz Edit] of R-0013 reagent (new from TF Test Kits), shook for 40 secs. It was not cloudy at all as the Taylor Youtube tutorial suggested. Slowly filling the Taylor test tube, the black dot remained visible, even fillet to the tip-top.
I thought I was close to switching from Dichlor to Liquid Pool Chlorine. Now I am not sure. Also, is this brand of chlorine OK? Klean Matters CDS Liquid Chlorinator 10% Ace Hardware was the only local store that sold individual gallons instead of two and four packs of gallons. The date code is Nov. 15 2023, so it is 5 months old. So it has 7 months before it reaches its half life, at which time the strength would drop 50% to 5% available chlorine. Assuming it was always stored at room temperature, is chlorine degradation pretty linear, so ≈ .42% drop in strength per month? If so, this 5 mo. old 10% chlorine would be ≈ 8% available chlorine. I assume I would enter the estimated 8% strength into Pool Math, instead of 10%, correct?
I believe I selected the proper permission to make my PoolMath App log available to TFP members who care to look at it. This is my first use of the app. I would appreciate any tips on how much info to log there. I have tested a lot these first few days trying to learn how much FC drops per bather load hour and how much Dichlor I need to add after a bather load period and just after time w/o use passes. I generally keep the temp set at 103º F. Temps this week have been warm, in the mid 70s. Hot tub is cover when not in use or adding chems. + 10-15 mins low speed mix time.
Caveat ::: Does CYA dissipate from a water sample over a few hours in an (almost) enclosed container at room temp? I had the ≈ 4 oz water sample taken a few hours before, in a clear 8 oz squirt condiment container, but the tiny squirt cap was not on the spout. Could the CYA have dropped to an unreadable level in these conditions? Am I doing something else incorrectly?
After balancing my 335 gal hot tub's fresh fill to: TA 50 ppm, FC 0, CH 250 ppm, I proceeded with the Dichlor/Chlorine to shoot for an initial FC level of 10 per Nitro's rec. Per the rec. of the PoolMath App, I added .8 oz (wt. via scale) of Dichlor (Spaguard Chlorinating Concentrate Sodium dichloro-s-triazinetrione dihydrate 99%) for initial shock.
.8 oz Dichlor added increased FC to 11.0 ppm (0+11)
1.2 oz Dichlor added over three days increased FC by 14.4 ppm cumulatively (4.4+3+3.6+3.4).
I must be misunderstanding Nitro's post. I thought he was saying each independent time that I raised the FC level by X, that CYA would be created of (.9 x X). Given that, I have increased FC cumulatively by 25.4, so CYA should be at (and should test at) ≈ 22.9 ppm (24.5 x .9). Do I have this wrong?
I filled a 1 oz squirt bottle to 7 ml (140 drops) of the room temp sample water, then added 7 ml
I thought I was close to switching from Dichlor to Liquid Pool Chlorine. Now I am not sure. Also, is this brand of chlorine OK? Klean Matters CDS Liquid Chlorinator 10% Ace Hardware was the only local store that sold individual gallons instead of two and four packs of gallons. The date code is Nov. 15 2023, so it is 5 months old. So it has 7 months before it reaches its half life, at which time the strength would drop 50% to 5% available chlorine. Assuming it was always stored at room temperature, is chlorine degradation pretty linear, so ≈ .42% drop in strength per month? If so, this 5 mo. old 10% chlorine would be ≈ 8% available chlorine. I assume I would enter the estimated 8% strength into Pool Math, instead of 10%, correct?
I believe I selected the proper permission to make my PoolMath App log available to TFP members who care to look at it. This is my first use of the app. I would appreciate any tips on how much info to log there. I have tested a lot these first few days trying to learn how much FC drops per bather load hour and how much Dichlor I need to add after a bather load period and just after time w/o use passes. I generally keep the temp set at 103º F. Temps this week have been warm, in the mid 70s. Hot tub is cover when not in use or adding chems. + 10-15 mins low speed mix time.
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