How To Calculate the Volume of Water in Your Swimming Pool for Accurate Chemical Adding

Know your pool volume for accurate chemical adding
Many pool owners do not understand the importance of knowing the volume of water in their pool. Why is this knowledge essential? The answer is simple. When you know the volume of water in your pool, you know how much of your chemicals to add. Adding too little or too much can cause all sorts of problems. Has it been a while since you were in math class? No problem. Fronheiser Pools is going to show you how to calculate the volume of water in your swimming pool for accurate chemical adding.

The Basic Formula

To perform the basic calculation to determine the volume of water in your pool, you are going to need to know your pool’s measurements. For a rectangular pool, measure the length and width of the pool. Calculate the average depth of the pool by adding the shallow-end depth plus the deep-end depth and divide by two. Example: shallow depth is 3, deep end is 9.  3 + 9 = 12 ÷ 2 = 6. The average depth is 6. Here is the formula:
  • First, multiply Length x Width x Avg. Depth = X
  • Next multiply X by 7.5, which is the number of gallons in one cubic foot of water
  • L 30 ft X W 15 ft X Avg. D 6 ft = 2700 X 7.5 = 20,250 total gallons of water in the pool
  If your pool is oval or round, the math is the same, but you will multiply by 5.9 rather than 7.5 to get your volume. If you have a very irregular-shaped pool, you can search online for the slightly more complex math formula, or the pros at Fronheiser Pools can help you calculate your volume.

Accurate Chemical Adding

Once you know the volume of water in your pool, you will be able to add the correct amount of chemicals. It is essential to be accurate when adding chemicals or the water balance will be off, potentially causing harm to bathers, the pool, and its equipment. The product package label will list the correct amount of each chemical to add. For example, your container of pool shock may advise adding a one-pound bag per 10,000 gallons of water each week. For your 20,250-gallon pool, you would double that.

Typical Pool Chemicals

Pool chemicals fall into three basic categories: sanitizers, balancers, oxidizers, and specialty chemicals. Sanitizers disinfect the pool water. Balancers adjust pH, alkalinity, calcium hardness, and cyanuric acid. Oxidizers (shock) are used to boost the effectiveness of the sanitizer. Specialty chemicals would be algaecides, clarifiers, stain removers, etc. Fronheiser Pools carries all your essential pool chemicals and offers convenient online shopping

Pool Chemical Calculation

The #1 thing a pool owner needs to know regarding pool chemical levels is what the average parts per million should be for the chemicals regularly added to the pool. A good test kit is the first line of defense in getting the proper water balance. Always carefully study your chemical’s packaging instructions to see the recommended dosage of each product per volume of water in the pool.  Fronheiser Pools carries the line of poolife® Pool Products, and that company has an excellent online document that goes into great detail on the subject of what the correct levels are and how to achieve the proper chemical balance in your pool water. They also reiterate the importance of carefully following the recommended instructions on the product packaging.  Fronheiser Pools understands that how to calculate the volume of water in your swimming pool for accurate chemical adding can seem overwhelming at first. Our professional staff is on hand to offer product suggestions, water testing, and problem-solving solutions to our customers. We invite you to stop in our showrooms in Bally and Sinking Spring with your questions. We would love to see you and assist you in having a successful swim season this year.  
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Fronheiser Pools

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