How to choose the right pool filter

The role of a pool filter is more like that of the kidney in your body. While other products like pool cleaners and chemicals work to kill bacteria and other contaminants, the filter removes them, leaving your pool clean. Without the filter, your pool will fill with debris and become cloudy, ultimately making swimming less fun. 

But which pool filter should you choose? You might be tempted to go for the cheapest filter, which is okay, but the goal should be to buy a filter that is easy to clean, traps contaminants, and lasts longer. If you’re looking for the best swimming pool filter and you don’t know where to start, we’re here to help you. This post will guide you through the process of choosing the perfect filter for your swimming pool.

What pool filter types are there to choose from?

Your search for the right pool or spa filters starts with understanding the various types available on the market. In most cases, your choice of pool filter is mainly up to you. Any type of filter will work for your swimming pool. Below, we look at the different swimming pool filters you can choose.

Sand filters

Sand pool filters are the most common type of pool filter. They are budget-friendly, easy to clean, and great for large pools because they don’t clog easily. Sand pool filters can be installed in-ground or above ground. As the name suggests, these swimming pool filters use sand to remove dirt and debris from the pool water. The water is sucked through the skimmers and pushed through the sand filter, where particles are grabbed.

Each grain of sand has rough edges that trap debris and contaminants. An outlet at the bottom of the filter allows clean water to flow back into the swimming pool. As more water continues flowing through the filter, the rough texture of the sand wears away, eventually making them incapable of capturing anything. This usually happens after 18 – 24 months. At this point, you’ll have to replace the sand.

Cartridge filters

Cartridge pool filters are ideal for small pools. They cost more than pool sand filters but can remove twice as much dirt. Cartridge filters are made of a plastic cylinder surrounded by a pleated, mesh-like material. Water from the swimming pool flows through the filter, where dirt and debris are grabbed. The clean water then flows back into the pool. The cartridge filter will need to be cleaned after some time.

To clean the filter, remove the cartridge from the tank, hose it, and put it back in the tank. Cartridge filters cost more, but they are easy to maintain, save water, are more energy-efficient, and can be replaced after 5 – 10 years. One thing to keep in mind is that the swimming pool pump and filter must work seamlessly.

Diatomaceous earth

Diatomaceous earth may not be as popular as sand filters, but it's the most efficient when it comes to water filtration. They filter the most amounts of dirt and debris compared to the two other filters. Water passes through a filter coated with diatomaceous earth to remove debris and particles. Because diatomaceous earth is finer than sand, it can remove smaller particles than sand filters.

What pool filter size should you choose?

The size of your pump will determine your pool filter size. A filter that is too small will break, and the pump may overheat. A large pool filter presents less risk than one with lower performance – always keep that in mind when shopping. It's also important to choose a filter that matches the capability of your pump. So, if you have a 42 GPM pump, purchase a filter that can handle 42 GPM or more.

You also need to take into account other features that can increase the total GPM of your pool. For large swimming pools (more than 60 GPM), you will need a large pool filter pump and pipes with a diameter of at least 5cm to handle up to 100 GPM.

How often should swimming pool filters be cleaned?

You can clean sand and diatomaceous earth filters in two ways. One is backwashing, which flushes dirt and debris out of the filter, so they work properly. Another way is to remove the filter and clean it manually. Below, we look at the approximate time frames for cleaning swimming pool filters.

• Sand filters: Backwash every 1 to 4 weeks and clean once a year

• Cartridge filters: Clean every 2 to 6 weeks. Also, deep clean once a year.

• Diatomaceous earth: Backwash every 1 to 3 months and deep clean at least once a year

While it's true that the number of times you need to clean your pool filter depends on your pool pump and filter type, there are obvious signs that a filter needs to be cleaned. This is because all filters clog as they fill up. Always check if your circulation flow rate drops or the back pressure rises. If the circulation decreases or the pressure increases, it’s time to clean the pool filter.

Feel free to browse our extensive collection to find the best pool filter.