How many gallons is my pool?

Shelley N

Well-known member
May 1, 2007
199
0
Denver, Colorado
#1
I've never been able to figure it out how many gallons my pool actually holds, so this weekend I tested the CL at 2ppm with the FAS-DPD, added 2 quarts of 6% and it rose to 4.5ppm. I tried to get the bleach calc to work backwards for me, but it wont. How do I figure this out? It's a 15 x 30 AG and I've heard so many different amounts of what it holds that I just thought I'd measure the rise after adding. Thanks.
 

The Mermaid Queen

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Mar 28, 2007
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Northern KY
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#2
Download BleachCalc here... it has a calculation that does it for you. If your water (not wall) is 3.5' deep, you have 9276 gallons. If you water is 4 feet deep, you have 10,602. If you have a deep end, you will have to find the avg. depth for your calc.

EDIT... just plugged in 10600, 1/2 gallon, and it said you should have gotten a 2.8ppm rise in TC, which is near your 2.5... I'd say you have around 11,000 gallons.
 

Shelley N

Well-known member
May 1, 2007
199
0
Denver, Colorado
#4
Forgot about the "other calcs" button. :oops:

Today, it's 44", so that's 3.66', so that's 9700.83 gal.

Golly, I thought it was more since the bleach calc says to add 2 quarts to raise 12,000 gallons 2.5ppm. That was the rise in ppm I got by adding 2 quarts anyway.
 

The Mermaid Queen

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Mar 28, 2007
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Northern KY
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#6
This is just weird! I used the pentair and did the oblong, and just used 15 feet for both diameters, and 3.6 depth, and got 10,935.
When I added up the 7.5 radius circle plus the 15' square, I got 10,846... different than the numbers you got.

Personally, if it was my pool, I would treat it as 10,000, and then adjust a little accordingly, if necessary.
 
#8
I've recently figured out that I have probably overestimated my pool gallonage. . . I don't know the manufacturer, but I have some documentation showing that the deep portion is 4'3" and the shallow part is 3'3". I assumed that meant the depth of the filled pool, but once I actually got into the pool, I realized it wasn't that deep! So those dimensions actually refer to the depth of the shell, not the water.

I recalculated with revised depths (30" and 42") and obtained gallonage figures around 7500-8200. Shucks, now I have to use a calculator to figure out how much chemicals to add! 10,000 gallons was so easy to work with <sigh>

Jules
 

RAA

LifeTime Supporter
Mar 28, 2007
46
0
The Woodlands, TX
#9
I think the only way to tell exactly how much water is in your pool is at fill time (unless you have a prefectly square or round pool) when you can look at your meter and record how many gallons it took to fill it up. I have an odd shaped pool and I can only guesstimate my pool volume. Some calculations put my pool at 18k and others put it at 15k. I just go with the 15k since that seems to be working very well. I didnt check the water meter when i filled it up :hammer:
 

Poseidon

Well-known member
May 24, 2007
148
0
Houston, Texas, USA
#10
Using software that I use everyday for my job (manufacturing), I come up with 10,997.65344 gallons. This is based on a pool 30 feet in overall length, with 7.5 feet (15 feet diameter) radius ends, and a continuous water depth of 3.66 feet. The surface area is 401.714351 cubic feet. Multiply that by 3.66 and you get 1470.274525 cubic feet. One cubic foot is 7.48 gallons (per Machinery Handbook, 23rd Edition). So 1470.274525 x 7.48 = 10,997.65344 gallons. I also calculated it manually, and came up with 10,997.6599 gallons, so pretty darn close.