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Easily Calculate the Gallon Volume of your Swim Spa
Proper water treatment and swim spa maintenance depend how many gallons of water your swim spa holds.
Use the formulas below, based on the shape of your swim spa, as a guide to approximate your swim spa’s water volume. Click here for a printable version.
Method #1 – Fill Time
The most accurate way to determine the volume of a swim spa, without fancy equipment, is by fill time.
- Use a stopwatch or wristwatch to time how long it takes to fill your swim spa. Convert minutes and seconds to total seconds and write it down.
- Use the same hose and pressure, and time how many seconds it takes to fill a one gallon bucket.
- Now divide the number of seconds it took to fill your swim spa, by the number of seconds it took to fill the one gallon bucket, and you will have the approximate water volume!
For example: If you filled your swim spa in 30 minutes (1800 seconds) and filled the one gallon bucket in 6 seconds, 1800 divided by 6 = 300 gallons.
Using a five gallon bucket will result in an even smaller margin of error. For example: You filled your swim 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 swim spa.
Portable Acrylic-Fiberglass Swim Spas:
(Take all measurements in inches)
Our formulas make it easy because you use the outside dimensions of your portable swim spa cabinet.
- For Square or Rectangular portable acrylic swim spas:
- For Round or Multi-sided portable acrylic swim spas:
*Results are estimated volume only. If needed, please consult with your swim spa manufacturer.
