what size of pool filter do i need

When it comes to keeping your swimming pool sparkling clean and clear, the pool filter is an essential piece of equipment. A good quality pool filter is designed to effectively remove dirt, debris, and other unwanted contaminants from your pool water, ensuring a safe and healthy swimming environment. But with so many different types and sizes of pool filters on the market, determining what size of pool filter you need can be a bit overwhelming.

In this article, we'll help you understand what size of pool filter you need for your specific swimming pool setup, and guide you through the process of selecting the right filter to help keep your water crystal clear all season long.

Understanding Pool Filter Basics

Before we dive into the details of selecting the right pool filter size for your swimming pool, let's review some basics of how pool filters work. There are three main types of pool filters:

1. Sand filters use a bed of fine sand to trap particles and debris as water passes through the sand.

2. Cartridge filters use pleated cartridges to trap debris as water passes through them.

3. DE (diatomaceous earth) filters use a fine powder made from the fossilized remains of diatoms to trap debris as water passes through the filter.

All three types of pool filters have pros and cons, but knowing the basics of each will help you make an informed decision when selecting a pool filter for your specific swimming pool setup.

Factor #1: Pool Type and Size

The first factor to consider when determining what size of pool filter you need is the type and size of your pool. Pool filters are typically sized according to the gallons of water they are capable of filtering per minute (GPM). This is based on the total volume of water in your pool, as well as other factors such as the desired turnover rate (how many times per day you want the entire volume of your pool to be filtered), and the flow rate of your pool pump.

To determine the size of your pool in gallons, simply use the following formula:

Pool Length x Pool Width x Average Depth x 7.5 = Total Gallons

For example, a rectangular pool that is 20 feet long, 10 feet wide, and has an average depth of 5 feet would have a total volume of 7,500 gallons (20 x 10 x 5 x 7.5 = 7,500).

Factor #2: Pump Flow Rate

The second factor to consider when determining what size of pool filter you need is the flow rate of your pool pump. The pump flow rate is measured in gallons per minute (GPM), and is the amount of water that the pump is capable of moving through the pool and filter system.

To determine the flow rate of your pool pump, consult the manufacturer's specifications or consult with a professional pool technician. Once you know the flow rate of your pump, you can select a pool filter that is capable of handling that flow rate.

Factor #3: Desired Turnover Rate

The third factor to consider when determining what size of pool filter you need is the desired turnover rate. The turnover rate is the number of times per day that you want the entire volume of your pool water to be filtered and circulated through the pool filter.

The recommended turnover rate for most swimming pools is at least once every 8 hours, or 3 times per day. To calculate the required flow rate for your pool based on the desired turnover rate, use the following formula:

Total Gallons ÷ Desired Turnover Rate (in hours) ÷ 60 = Required GPM

For example, if you have a 15,000 gallon pool and want a turnover rate of 8 hours, the required GPM would be:

15,000 ÷ 8 ÷ 60 = 31.25 GPM

Factor #4: Filter Maintenance

The fourth factor to consider when selecting the right pool filter size is the maintenance requirements of the filter. Depending on the type of pool filter you choose, there may be different maintenance requirements and costs associated with cleaning and replacing filter media.

For example, sand filters require periodic backwashing to remove built-up debris from the sand bed, while cartridge filters need to be periodically cleaned or replaced. Consider the ongoing maintenance costs and requirements of the filter when selecting the right size for your pool.

Factor #5: Budget

The fifth and final factor to consider when selecting the right pool filter size is your budget. Pool filters can range in price from a few hundred dollars for a basic sand filter to several thousand dollars for a high-end DE filter system.

While it's important to invest in a good quality pool filter to ensure proper filtration and safety, you should also consider your budget and choose a filter that meets your needs without breaking the bank.

In conclusion, selecting the right size of pool filter requires careful consideration of your pool size, pump flow rate, desired turnover rate, maintenance requirements, and budget. By understanding these factors and consulting with a pool professional, you can choose a pool filter that will keep your water crystal clear and healthy all season long.