Starting with a swamp - order of operations?

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
20,311
Northern NJ
Your TA of 110 is not a big deal for a vinyl liner pool with no SWG.

And with your 7/4 test I would have just added Borax. You only needed to get your TA to 50 or above to be safe.
  • Baking Soda = big TA change, small pH change
  • Borax = Big pH change, small TA change
  • Soda Ash/Washing Soda = big pH change, big TA change.
 

CrystalRiver

Well-known member
Jun 19, 2020
297
Massachusetts
Effects of Adding says TA should have increased by 14 from Borax and 20 from baking soda. 40+14+20 is 74, not 110. That's what I don't understand, why I got double the TA rise that I was expecting.
 

CrystalRiver

Well-known member
Jun 19, 2020
297
Massachusetts
Having learned more about the TA test, I suspect my FC was too high to get an accurate result. Two drops of (R-007? The first one) neutralizes about 15 ppm chlorine. My SLAM level is higher than that.

At any rate, today the water is CLEAR. I can see the bottom on the far side of the pool. I'm still SLAMming (lost 8 ppm from 8P-8A last night). Swimmers were in just before dark last night, and I smelled the "pool smell" when I walked up this morning. I expected high CC but it was 0 or maybe just a tidge - well less than 0.5.

With clear water and no CCs, I'm just waiting for the OCLT. But finally, after a bit over a month of chlorinating, and a few weeks of plumbing before that, we're able to enjoy the ool.
 

CrystalRiver

Well-known member
Jun 19, 2020
297
Massachusetts
Passed the OCLT so now I can declare the Ool is officially clean!

Now I need to figure out a dosing schedule that makes sense. We have a high swimmer load for the size of the pool - often 7-8 people in 7K gallons, for hours at a time. Ool has been consuming 7-8 ppm FC per 24 hours for the past couple days, with 0-1 ppm overnight loss and 0-0.5 CC.

Latest test results:
FC 8.0 8/8
CC 0.5 8/8
pH 7.6 8/7
TA 120 8/6
CYA <30 8/7
Temp 78-83 lately

I'm working on bringing my CYA up to 40. At CYA 40, FC target is 5-7 with a minimum of 3. How would you go about scheduling and targeting dosing, with loss of 7-8 ppm per day?
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
33,291
Laughlin, NV
How would you go about scheduling and targeting dosing, with loss of 7-8 ppm per day?
On the days of high bather load, plan to test and add chlorine twice a day. Try once around noon and again in the evening. I suspect once your raise your CYA level you may find it unnecessary, but data from testing will tell you that.