Proper water treatment and spa maintenance are dependent on the size
of your spa, so it’s important to know the capacity of your spa in
terms of gallons. Use the following formulas based on
the shape of your spa as a
guide to approximate your spa’s volume. Click here for printable version
| Method #1 - Fill Time |
| The most accurate way to determine the volume of a
spa, without fancy equipment, is by fill time. First, using a stopwatch
or wristwatch time how long it takes to fill your spa. Convert minutes
and seconds to total seconds, and write it down. Then, using the
same hose and pressure, time how many seconds it takes to fill a
1-gallon bucket. |
Now divide the number of seconds it took
to fill your spa, by the number of seconds it took to fill the gallon
container, and you will have the approximate water volume! For example:
You filled your spa in 30 minutes (1800 seconds) and filled the
one gallon container in 6 seconds. 1800 divided by 6 = 300 gallons. |
Using a five gallon bucket
will result in an even smaller margin of error. Using the above
example with a five gallon bucket: You filled your spa in 1800
seconds, and filled the five gallon bucket in 30 seconds. 1800
divided by 30 = 60 five gallon buckets, or 300 gallons. |
|
| Method #2 - Dimensional |
| The dimensional method is not as accurate as the fill-time
method, but is a quicker way to determine the approximate volume
of any spa. |
Portable Acrylic-Fiberglass Spas:
(Take all measurements in inches)
Our formulas make it easy because you use the outside dimensions
of your portable spa cabinet.
• For
Square or Rectangular portable acrylic spas:
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| • For Round or Multisided portable acrylic spas: |
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| * Results are estimated volume only. Consult with
manufacturer |
In-Ground Spas, Soft Spas, & Wooden Hot Tubs:
(Take all measurements in inches)
These types have
fewer interior water-displacing features, so
this formula takes that into account.
• For Square or Rectangular types:
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| • For Round, Irregular, or Multisided types: |
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| * Results are estimated volume only. Consult with
manufacturer |
