Trying to figure water volume by poolmath and estimator.

[borjis]

So I have the blue prints to my pool (built 1973) but unfortunately the company
that did the blue prints never filled out the volume descriptor.

Somehow I had calculated the volume to 17,000 gallons and its been so long
I had forgotten how I came about that figure.

One thing I know for certain:
in the last 10 months I have had this house/pool, when I add 1 gallon of 8.25% bleach
it ALWAYS raises the FC by 3.

going by the pool math calculator and setting my current chemical readings then
setting it so that 1 gallon of bleach will raise it by 3ppm, I get a volume of: 27,000 gallons.

However if I go to the bottom of the pool math page and use the estimator to put in
my pools' measurements I get a volume of: 23,000 gallons.

I don't need to know exactly what the volume is but would be nice to know the general volume of it.

Would it be safe to say it is somewhere between the two? or is the pool math calculation more
likely the accurate one?

Again, every time I add 1 gal of 8.25% the free chlorine goes up 3 ppm.

thanks.

 

[jblizzle]

Something does not jive.
If you are getting a 3ppm rise for a 121oz of 8.25%, that would point to a 27k pool.
But, if you had 32x19 rectangle, the average depth would have to be 6 feet to get up to 27k. And yours is not a rectangle so the depth would have to be deeper to be 27k.

How old is the bleach? How is it stored? Maybe it is weak? How soon after adding it are you testing?

Usually the chemical additions will let you zero in on the volume pretty well, but in this case it does not make sense if your pool measurements are correct.

 

[borjis]

Something does not jive.
If you are getting a 3ppm rise for a 121oz of 8.25%, that would point to a 27k pool.
But, if you had 32x19 rectangle, the average depth would have to be 6 feet to get up to 27k. And yours is not a rectangle so the depth would have to be deeper to be 27k.

How old is the bleach? How is it stored? Maybe it is weak? How soon after adding it are you testing?

Usually the chemical additions will let you zero in on the volume pretty well, but in this case it does not make sense if your pool measurements are correct.

Bleach is always store bought fresh at Safeway or Fred Meyer. Winco bleach is weaker and I don't use now. The Winco would always raise 2.5 pom or less. 3 pom for the Safeway Mordred Meyer was always 3 pom consistent.

I might store it up to 7 days in a cool shelf.

My pool is 9 feet deep. 3 feet in shallow to a rapid drop to 9. Its a tear drop shape. Some have called my pool a diving well. Lol.

But the 3 pom rise after adding then running pump 2 hours then testing for FC has always been consistent

- - - Updated - - -

Haha pom = ppm
Darn phone spell check.

- - - Updated - - -

So pool math being accurate plus odd shape and rapid depth from 3 feet to 9...most likely 27k gallons?

 

[jblizzle]

So it is pretty deep ... still seems like 27k is too much for 19x32

 

[borjis]

Well, I think I'm going to call it 23,000 gallons. I know it's more than 17,000 but less than 27,000.

I'm doing a SLAM and needed 41 ppm FC to defeat the pesky recurring Mustard. (cya = 70)

I started with FC: 5.5 ppm today and added 12, 121 oz bottles of 8.25% bleach this evening

I estimated that to be around 45 ish and it came out to 47 ppm after running the pump 2 hours.

Pool math says that would be the case for 23,000 gallons and the estimator from my measurements
says the pool is 22,500.