how to size pool filter

Author: PoolKing - Pool Sand Filter Manufacturers

How to Size Pool Filter

Pool filters are essential components in keeping your swimming pool clean and safe. Their primary function is to remove dirt, debris, and other impurities in your pool water. Choosing the right size pool filter is crucial for maintaining water clarity, preventing maintenance issues, and prolonging the life of your pool equipment. In this article, we will guide you on how to size a pool filter and provide useful tips on how to make the right choice.

Understanding the Different Types of Pool Filters

Before sizing a pool filter, it's essential to know the different types of filters available in the market. There are three types of pool filters: sand filters, cartridge filters, and diatomaceous earth (DE) filters.

Sand Filters: Sand filters use sand as a filtration medium to trap impurities. They are popular because of their low maintenance and affordability.

Cartridge Filters: Cartridge filters work by trapping impurities in the fabric, and they are known for their efficiency and high flow rates.

DE Filters: DE filters use fossilized remains of diatoms to trap impurities. They are the most efficient type of filter but require more maintenance than sand and cartridge filters.

Five Steps to Sizing Your Pool Filter

Step 1: Determine Your Pool Size

The first step in sizing a pool filter is to determine your pool size. This can be done by measuring the length, width, and depth of your pool. Multiply these three values to come up with the number of gallons your pool holds.

Step 2: Calculate the Flow Rate

The flow rate is the amount of water that flows through your pool filter in a given period. To calculate the flow rate, divide the number of gallons in your pool by the turnover rate. The turnover rate is the time it takes for your pool's water to circulate through the filter system completely.

Step 3: Determine the Filter Type

Once you have calculated the flow rate, you can determine which type of filter is suitable for your pool. Sand filters are ideal for pools with a flow rate of 15 gallons per minute (gpm) or less. Cartridge filters are suitable for pools with a flow rate of 30 gpm or less, while DE filters are recommended for pools with a flow rate of 60 gpm or less.

Step 4: Choose the Filter Size

Choose the filter size based on your pool size and filter type. For sand filters, the rule of thumb is to choose a filter that has a flow rate of 1 gallon per minute per square foot of filter area. For cartridge filters, choose a filter that has a surface area that is at least 1.5-2 times the size of your pool. For DE filters, choose a filter that has a surface area that is between 2-4 times the size of your pool.

Step 5: Consider Other Factors

Other factors to consider when sizing your pool filter include the type of pump you're using, the number of swimmers and their frequency, and the environment around your pool. If you have a high bather load or live in a dusty area, you may need a more powerful filter.

Conclusion

Sizing a pool filter can be daunting, but it doesn't have to be. By following the steps outlined in this article, you can choose the right size pool filter that ensures clean and safe pool water. Remember, a well-sized filter system enhances the performance of other pool equipment, reduces maintenance costs, and provides you with many years of enjoyment in your pool.