I have been trying to more accurately calculate the volume of my pool, which is tough because it has an unusual shape... I had a rough estimate from using the dimensions and various online calculators, but was suspicious of the result. Then it occurred to me that I could use chemistry to figure it out... I'd like to run this by y'all to see if you think it holds water (pun intended).

Recently I added two jugs of Clorox to my pool, which amounts to 1.89 gallons of a solution containing 7.85% available chlorine. The next day (after 24-hours circulation) I retested my pool chemistry and observed a 5.9 ppm increase in free chlorine. Then I plugged this data into the dilution equation:

(C1)x(V1) = (C2)x(V2)

where C = concentration and V = volume

Therefore:

78,500 ppm x 1.89 gallons = 5.9 ppm x [unknown volume]

Divide both sides of the equation by 5.9 and then solve for X, which yields a volume of 25,146 gallons. This is pretty close to the 26,000 gallons I have been previously assuming based on various estimates from width and depth...

So have I missed anything here, or is this a correct methodology and result?