Calculate pool volume from ppm salt

[Ibelyle]

640 lbs of salt resulted in 3900 ppm. How many gallons? (Owner told me pool was 28,000)

 

[Ibelyle]

Recently, a pool owner advised me that his pool held about 28,000 gallon. I added 640 lbs of salt aiming to establish the level at slightly less than 3200 ppm. 48 hours later the water tested at 3900 ppm. Using the 267 lbs/10k gallons = 3200 ppm, I arrived at +/- 19,700 gallons as the actual volume of the pool. This difference doesn’t seem right, and I feel like I must have missed something.

 

[HermanTX]

If you do just the pure math, on
PoolMath app. The volume of 19,600 gals will produce 3902ppm with 640lbs of Salt.
Are you sure you started with ZERO salt ppm?

 

[HermanTX]

Answered in your other post with same question.
Most pools have some salt level when using liquid chlorine or other chemicals so you may have had salt to start. Also how are you testing salt? The best kit is K-1766. Being off by 10,000 gals seems a lot. What shape is your pool if you can do measurements.

 

[Ibelyle]

If you do just the pure math, on
PoolMath app. The volume of 19,600 gals will produce 3902ppm with 640lbs of Salt.
Are you sure you started with ZERO salt ppm?

This was a new install w/ 0 salt. Using algebra (for the first time in years) based on the 267 lbs / 10k = 3200 ppm formula, I came up with 19,692 gals. I use a Lamotte Pocket Tester and calibrate it with a 3000 ppm standard. It has alway proven quite accurate and very convenient. It is with a sigh of relief that I send my sincere appreciation and best wishes to you and yours. Regards, Lyle

 

[mknauss]

No body of water has 0 salt unless it is from an RO unit.

 

[Ibelyle]

I appreciate the reminder.

 

[duraleigh]

Two strikes........starting with an unknown quantity of salt AND the precision of the salt test is not good enough to give you a really meaningful measure of the pool volume.

Is it odd shaped or can it be calculated by dimension?