Math Trouble

[April]

This may be a stupid question but........Im trying to figure out how many gallons are in my friends pool that I'm helping her slam. I thought I could figure it out by how many gallons of chlorine I had added to get her to her slam level but math is not my strong point. So any help is appreciated.

She thinks the size is a 20x40 IG Grecian. Shallow end is 4' deep end is 8'. But she is not positive.

So I added:
4 gallons of chlorine 10%
Raised her FC to 13.

Is it possible to figure out the gallons this way?

 

[jblizzle]

Not very exactly. Since you do not know the exact strength of the bleach.

Assuming it is really 10% and you started at 0ppm ... PoolMath estimates it would be 31k gallons.
Although using the volume calculator, it could be a little more than that if the dimensions are correct.

 

[Divin Dave]

Hi April,

For calculating how many galollons in a pool (or any other rectanular or square container)
the formula is L*W*D = cubic feet of volume

There is 7.47 gallons in 1 Cubit Foot of water - so,
Gallons = Cubic Feet * 7.47

Or - why not just use pool math to help you?
Towards the bottom of pool math is a volume calculator.
Just measure the length and width of the pool. For the depth, do an average. Deep End + Shallow end divided by 2.

Or, you can play around with pool math by changing the volume and using the 4 gallons raising the FC to 13 and nail it that way.
http://www.troublefreepool.com/calc.html


If you want to calculate the pool volume chemically, then here is the best way to do it. (this should impress your friend!)
A Chemical Way of Calculating Pool Volume

hope this helps,

 

[April]

Thank you Jason and Dave.

I didn't know if pool math would be correct because the sides of the pool slope in. Like this \_/.

 

[Divin Dave]

Yup,
it does account for the slope. to some extent. Not all pools will be exactly equal slopes though, but pool math should easily get you within a few hundred gallons.
Its easy enough to tweak it from there.

Thank you Jason and Dave.

I didn't know if pool math would be correct because the sides of the pool slope in. Like this \_/.

 

[mas985]

Just to be precise, there is 7.48 gallons/cu-ft.

 

[April]

Thank you everyone. I'll use 28k to start out with and adjust from there.