Another 'Chemical Way to Calculate Pool Volume' Thread

[nharwood]

After 11 months of construction our pool was finally filled about a month ago. The pool builder construction plans calculated the total volume of our pool as 11,000 gallons. The folks that came out to do the initial startup / equipment checkout / chemical balance said they were told it was a 12,000 gallon pool. For the past month I have been using 11,000 gallons for all of my chemical balancing math. I have noticed that the results (of pH or chlorine changes) were less than pool math suggested.

Now that the plaster has cured for about 30 days I needed to add salt to raise salt from 400 ppm to 3,200 ppm. Pool math suggested a little more than 6 bags so I added 5 to be safe. I am now at 8 40lb bags added and my salt level is still only at 3,000 ppm. (measured both by the iAquaLink and Taylor test kit). Reverse engineering the math, my 'calculated' volume for that salt rise is closer to 14,700 gallons.

I've seen other threads which suggest TA or Chlorine could be used to come up with a calculated volume, but what do you think about my salt method above (even if just for my own situation)? Should I start to use 14k or 15k gallons for pool math calcs going forward? I only ask because designing a pool in CAD software should not be off by 4,000 gallons when every other dimension was within an inch or two.

 

[AQUA~HOLICS]

I would use the lower of the two calculations so not to over treat the water and adjust if your not meeting your target. Next time you re fill the pool from being empty take a picture of your water meter before and after filling this is the more accurate than any formula.

 

[Bperry]

After 11 months of construction our pool was finally filled about a month ago. The pool builder construction plans calculated the total volume of our pool as 11,000 gallons. The folks that came out to do the initial startup / equipment checkout / chemical balance said they were told it was a 12,000 gallon pool. For the past month I have been using 11,000 gallons for all of my chemical balancing math. I have noticed that the results (of pH or chlorine changes) were less than pool math suggested.

Now that the plaster has cured for about 30 days I needed to add salt to raise salt from 400 ppm to 3,200 ppm. Pool math suggested a little more than 6 bags so I added 5 to be safe. I am now at 8 40lb bags added and my salt level is still only at 3,000 ppm. (measured both by the iAquaLink and Taylor test kit). Reverse engineering the math, my 'calculated' volume for that salt rise is closer to 14,700 gallons.

I've seen other threads which suggest TA or Chlorine could be used to come up with a calculated volume, but what do you think about my salt method above (even if just for my own situation)? Should I start to use 14k or 15k gallons for pool math calcs going forward? I only ask because designing a pool in CAD software should not be off by 4,000 gallons when every other dimension was within an inch or two.

I think the salt test has an error of +/- 200ppm so be careful making assumptions.