What Size Filter Do I Need For My Pool

Picking the Best Filter Size for Your Puddle

I've never understood why people buy the biggest pump they tin can afford, and so get small on the pool filter. I telephone call it the "5-8 mentality." They want the biggest engine, in the smallest car.

To save you time in your valuable day, I'll give you the moral of the story upfront. The main point of this post is to"Go Big."

Choosing a larger pool filter makes sense, and it has many benefits:

Longer filter cycles, or time between backwashing
Less bypass of fine particles
Greater filtration of the water
Faster cleanup of water issues
Longer-lasting filter media

Sizes of Residential Pool Filters

Filters are commonly sized by the foursquare footage of surface area. It makes sense: The more square anxiety of filter media you have, the better the filter functioning will be. Only it gets tricky when you endeavour to compare the three different types of pool filters to each other.

That's because they all trap clay and debris in different ways — they're like apples and oranges!

Don't let this confuse y'all, though. Within each filter type, at that place are typically four or five sizes.

Of these sizes, the smallest are suitable for aboveground pools, the mid-range ones can be used for pocket-sized pools around xv,000 gallons, and the large filters work best for pools above 25,000 gallons.

To add together to the confusion are the manufacturer's listed turnover rates for their pool filters. These are usually listed on product information pages, and they show the maximum flow rates for the filters.

This snippet below, from our Hayward Star-Clear filter folio, seems to suggest that a 25-square-foot filter can have care of a 12,000-gallon pool, and I can tell you that is not the case. Non even shut.

Sand Filters

For sand filters on in-ground pools, I like to use a 30-inch tank bore, which has a 4.nine sq. ft. filter surface area and holds 600 pounds of sand. For small pools (under 20,000 gallons), I might advise the side by side size down (24″ tank) if the budget is tight. But never get smaller than this for an in-footing pool.

Cartridge Filters

I have a rule of thumb for cartridge pool filters: 100 sq. ft. of filter surface area per 10,000 gallons of puddle water, as a minimum. I like to run across the 400 sq. ft. models on in-footing pools above 25,000 gallons. These can get an entire season without cleaning in most cases.

DE Filters

Because diatomaceous world filters offer the nigh superior type of filtration, people tend to go pocket-size and buy a 24 or 36 sq. ft. DE filter. Ugh … no, GO Large! Don't use anything below a 48 sq. ft. filter, and if your pool is over 25,000 gallons, go with the big option (the 60 sq. ft. filter).

For the average in-footing puddle, if coin is available, buy a big DE filter and be done with information technology. If your budget is squeezed thin this twelvemonth, buy the thirty″ sand filter.

Pump Size to Filter Size

With a big pool filter, in that location'due south no worry nigh the pump beingness too large for the filter. As well, don't worry if your pump seems undersized for a larger puddle filter — this is rarely the instance. When the pump is likewise large, however, it can hateful all sorts of trouble. Clay can be pushed through the filter, internals can get crushed or cracked, and high force per unit area makes for a irksome, inefficient and potentially hazardous situation.

Filter Size to Pool Size

Another dominion of thumb I take for pool filter size is to expect at the swimming puddle size in gallons. If you've never calculated this earlier, take some measurements. The formula isLength ten Width ten Average Depth ten seven.5, for rectangular pools.For oval pools, change the multiplier from seven.5 to five.9.

NSF Standard 50

Filter manufacturers size all three systems in accord with the National Sanitation Foundation (NSF) Standard 50 "Circulation Organisation Components for Pond Pool."

Loftier-rate sand:Max flow rate 25 GPM per square foot of surface expanse, normally sized between 15 and twenty GPM per sq. ft. A minimum flow charge per unit of 11 GPM per sq. ft. is required to utilise the torturous path filtration of depth type filter media. Menses rates over 25 GPM tin lead to channeling.

Diatomaceous World (DE):Max menses charge per unit two.5 GPM per square human foot of surface area, ordinarily sized at 2 GPM per sq. ft. Proper catamenia charge per unit and pressure are essential to assure a uniform cake formation on the support grids.

Cartridge:Max period rate one GPM per square foot of area; can exist sized between 0.25 GPM and 1 GPM per sq. ft.

Here's some pool filter size recommendations by type. Lucifer your pool size in gallons (or less) with the filter model number. And, don't be afraid to go ane size bigger!