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Best pool filter

Which pool filter is best?

There’s no greater pleasure during a summer heatwave than relaxing in the cool waters of your own pool. That is unless algae growth has your pool looking more like the Swamp Thing’s studio apartment than a suburban oasis. If your pool is being overtaken by green slime, then a new pool filter is probably in order. A good pool filter is essential to keeping your water crystal clear, and if you’re in the market for a new one, there’s no better place to start than right here.

Check out our helpful buying guide to find the best pool filter to restore your summertime bliss. We also included reviews of a few of our favorites, including our top choice from Hayward.

What to know before you buy a pool filter

The three main types of pool filters are sand filters, cartridge filters, and D.E. filters.

  • Sand filters use #20 silica sand to filter out pollutants. The water enters from above and seeps through the sand, which traps particles as the water exits below the sand. Sand filters are inexpensive and simple to maintain; the sand is cleaned off the particulate by “backwashing.” They last for approximately five years. They are, however, the least energy-efficient of any pump.
  • With cartridge filters, water passes through a thick tube that contains a pleated material (similar to a car oil filter), which traps the unwanted particles inside. Cartridge filters work well at lower motor speeds and don’t require backwashing, unlike sand filters. They do require more work than sand filters, and they last approximately three years.
  • D.E. filters use diatomaceous earth to clean the water. Diatomaceous earth is composed of the fossilized remains of diatoms, which are found in the ocean and soil. D.E. filters incorporate some of the principles of both sand and cartridge type filters. They do the best at cleaning water, as they filter the smallest particles of all the filter types. They are, however, the most labor-intensive type of filter.

Regardless of the filter type you opt for, a pool filter requires a pump to function. The pump is what draws the water through the filter and pushes it back out into the pool. To determine what size pump you’ll need, you will need to determine the flow rate and resistance number for your pool. Flow rate refers to the gallons per minute your pump needs to move in order to clean all of the pool water within an eight-hour period. Resistance is a calculation based on the distance between the pump and the skimmers and drains, as well as the number of skimmers and drains.

You will also need to determine the type of mount you want, as well as whether you want a 110-volt or 220-volt pump. Once you’ve determined these items, then you’ll know what type of pump you’ll need to accompany your filter.

How much you can expect to spend on a pool filter

Most pool filters cost somewhere between $60 and $1500. The difference in price is based mostly on the filter’s total square-foot cleaning capacity.

Pool filter FAQ

Are chlorine pools better than saltwater pools?

A. Neither is necessarily better than the other. In a chlorine pool, however, chlorine is added to the water directly whereas saltwater pools create their own chlorine by turning the salt into chlorine via electrolysis.

How high should the water level be in my pool?

A. As a general rule, you should try to keep the water level of your pool approximately halfway up the opening of your skimmer basket. This will guarantee that both the skimmer and the pump will work their best.

What are the best pool filters to buy?

Top pool filter

Hayward W3DE3620 ProGrid Diatomaceous Earth Pool Filter

Our take: This filter will keep your pool “hotel clean.”

What we like: The perfect combination of power and sturdy build, it’s a workhorse in every sense of the word. First-rate results.

What we dislike: The instructions can be somewhat difficult to follow.

Where to buy: Sold by Amazon

Top pool filter for the money

Blue Wave Sand Filter System for Above-Ground Pools

Our take: A filter that will get the job done on a budget.

What we like: Easy to clean, and good water flow.

What we dislike: Occasional malfunctions.

Where to buy: Sold by Amazon

Worth checking out

Intex Krystal Clear Cartridge Filter Pump

Our take: Inexpensive choice, though you’ll have to add peripherals.

What we like: Quick and easy installation and double-insulated walls are nice benefits for this cost-effective pick. Not much maintenance is needed.

What we dislike: Motor is not as powerful as some of the other options. Hoses and adapters must be purchased separately.

Where to buy: Sold by Amazon


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Adam Reeder writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.

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