The best filter balls, compared.
Top pick: STEEIRO filter balls, 1800 g Best value: Bomxmon filter balls, 1.54 lb – About £9.99, with 1.54 lb within 5 per cent of 720 g, a wash line on the listing, and four UK texts under 4.8 from 5. Updated October 2026.
Pool filter balls are loose polyester or polyethylene fibre spheres that sit in a sand-filter tank instead of graded silica sand. In the UK they are bought mainly for above-ground and seasonal pools, because a few hundred grams replaces a 10–25 kg bag of sand. You still need a clear view of the bottom and a separate chemical routine. Quality is whether the title weight and the technical weight agree. Ten of 50 saved texts are labelled United Kingdom. The [filter balls buying guide](/hub/pool-care/filter-balls/sub/filter-balls-buying-guide) sets out the gram tables before you match a slogan to your pump. Cartridge nets, spa cartridges and pond wool are different housings. Filter glass is the other sand alternative, and it is still a granular bed.
Pool filter balls are loose polyester or polyethylene fibre spheres that sit in a sand-filter tank instead of graded silica sand.
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Personal buying guide
Question 1 of 2
What does the pump manual allow?
The STEEIRO pack is the heaviest title in this set, 1,800 g at £13.99, with a technical line of 1.82 kg. One bullet says 4 lb replaces 150 lb of sand and, in the same sentence, that 1,800 g equals 65 kg. The title says Lightweight Blue Filter Balls and ends with (White). The bullets say the balls can be machine washed in a laundry bag; they do not say the bag is in the box, and they do not name the polymer. amazon.co.uk shows 5.0 from 5 reviews, and the only saved text is a United Kingdom note about a paddling pool. Saltwater use, ball diameter, and whether they are safe for fish are unanswered. Four of the five ratings have no text, so the star line is five clicks rather than five descriptions. Ranked 22 in Pool & Hot Tub Filters on the saved page, it is still a generic bag without an SX or Bestway model code.
Pros
Cons
Best for: You want the heaviest generic bag in this comparison for a small seasonal pool, and you can check the colour when it arrives.
Less suitable: You need a published fill for an SX2100 or a Bestway flow rate, or a review file longer than one paddling-pool note.
Specifications
Common questions
Are they blue or white?
The title says Lightweight Blue Filter Balls and ends with (White). The file does not add a colour photo caption that settles it.
Can they go in a saltwater pool, and are they safe for fish?
Both questions are on the page and unanswered. The bullet says the material is non-toxic. It does not mention salt water or fish.
How are they washed?
The bullet says they can be machine washed and reused in a laundry bag. It does not say a laundry bag is in the box, and it does not give a temperature.
The Windspeed listing is £11.99. The title and the model number say 1,400 g, equivalent to 50 kg of sand, and the technical line says 700 g. The bullet says about 200 balls, a diameter of about 4.8 cm, polyester fibre, and filtration of 3–5 microns, which is the seller’s wording and not a lab result in this file. amazon.co.uk shows 4.8 from 16 reviews, with three United Kingdom texts saved. Those owners describe gunk caught over about three weeks, a ten-minute machine wash with no fabric conditioner, a full bag in a Bestway 58599, and a summer in a sand filter alongside chemicals. Jade says not to use backwash, and suggests a second set if you do not want the pool waiting while one set is in the wash. Saltwater use is unanswered, and the bullets themselves do not say washing machine. You cannot treat the title’s 1,400 g as the weight that will arrive.
Pros
Cons
Best for: You already know you want about 700 g, you will weigh the bag, and you will treat the no-backwash note as that owner’s advice.
Less suitable: You need the title’s 1,400 g to be the weight in the box, or a pump maker’s gram table.
Specifications
Common questions
Is the pack 1,400 g or 700 g?
The title and the model number say 1.4 kg. The technical details line says 700 g. The file does not say which one arrived.
How many balls are in the bag?
The bullet says about 200, with a single diameter of about 4.8 cm. That question is still listed as unanswered on the page.
What filtration size does the seller claim?
The bullet says the balls can filter dirt and particles of 3–5 microns. That is the seller’s wording. This file has no lab result.
The Bomxmon pack is listed at £9.99 with a title of 1.54 lb, about 699 g, against a technical line of 720 g. The title says the bag replaces 75 lb of filter sand, and the bullets call the balls washable and reusable for swimming pools, aquariums, and mainstream sand filters. amazon.co.uk shows 4.8 from 5 reviews, and all four saved texts are from the United Kingdom. Those buyers describe a sand filter, a hot-tub skimmer, and a pond filter, and one says a neglected sandy pool looked usable again. Chris paid £15.99 when the order arrived, which is not the £9.99 saved on this file. The material is not named, the ball diameter is an unanswered question, and no storage bag is confirmed in the box. The four texts do not describe torn balls or fibre in the water, and one pond owner said it was too early to judge a lasting difference.
Pros
Cons
Best for: You want a generic bag around 700 g for a small sand filter, and you will check the fill against your pump manual rather than the 75 lb slogan.
Less suitable: You need an Intex gram table, a named polymer, or a pack whose maker publishes the wash temperature.
Specifications
Common questions
Can they be used in saltwater?
The page asks and does not answer. The bullets do not mention salt water.
What is the diameter of each ball?
The page asks and does not answer. The technical line gives the parcel as 5 x 4 x 1.4 cm and 720 g, not a ball diameter.
Is a storage bag included?
The page asks and does not answer. The bullets say no complicated tools are needed to put them in a sand filter.
The Intex 29045 is a 500 g bag of fibre balls at £10.99, and the bullets say that bag stands in for 18 kg of silica sand in a sand filter pump. On amazon.co.uk the listing is 4.5 from 1,004 reviews; of 50 texts saved in the file, 10 are labelled United Kingdom, so that star line is not a British sample. UK reviewers describe a lighter fill than sand, a 30 degree machine wash that came out white after about a month, and a heater that stopped cutting out overnight once flow improved. One UK buyer says the bag is all right for a smaller filter and less convincing on a larger pool, where the balls need washing or changing more often. Another needed more than a single order and kept older balls in use. The catalogue material field says Glass while the title says fibre balls, and the technical line is 510 g against a 500 g title. Intex’s own support table, not this bullet, is the fill to follow, and the balls are not a cartridge.
Pros
Cons
Best for: You have an Intex sand pump whose published table calls for about 500 g, and you will wash the balls the way Intex prints.
Less suitable: You need the SX2100’s 650 g line, a cartridge pump, or a Bestway hand-rinse routine.
Specifications
Common questions
What does Intex say this bag replaces?
The bullets say a 500 g bag is equivalent to 18 kg of silica sand and can stand in for sand, glass, or other filter media in a sand filter pump.
Are they machine washable?
The bullets say yes. One UK review in the file used a 30 degree wash. The listing does not answer the special-maintenance question in its own Q&A block.
Why does a field say glass?
The catalogue material type on this fibre-ball listing says Glass. The title and the item type say fiber ball filtration media. The file does not resolve that.
The yunwailc bag is 200 g of high-density polyester balls at £8.99, sold as replacing 5 kg of ordinary filter sand. The technical line says 190 g, the item model is YWJY1085, and the part number is YWJJYQ87. The bullets say a hand scrub or a machine wash, and they present less backwashing as a benefit without forbidding it. amazon.co.uk shows 4.0 from 1 rating, and the raw file saved no review text. Compatibility with all sand filters, and how often to replace the balls, are unanswered. The rank line sits under Pool & Hot Tub Filter Cartridges, while the bullets name backyard pools, fish tanks, and aquariums. First available is 7 July 2026. At more than twice the price of the 200 g Rakiuty, you are looking at one star and a 10 g gap between the title and the technical weight.
Pros
Cons
Best for: You want a small polyester bag and you will confirm the 190 g line when it arrives.
Less suitable: You want a review record, an Intex model number, or a heavier fill.
Specifications
Common questions
Do they fit every sand filter?
The page asks that and does not answer it. The bullets name backyard pools, fish tanks, and aquariums.
How do you clean them?
The bullet says a hand scrub or a machine wash. It does not give a temperature or a replacement interval.
Why do the model numbers differ?
The item model number is YWJY1085 and the part number is YWJJYQ87. The rank line sits under Pool & Hot Tub Filter Cartridges.
The Rakiuty 200 g bag is £3.99, and the title weight and the technical line both say 200 g. The bullet says that 200 g is equivalent to 4 kg of filter sand, names acrylic, polypropylene, and polyester yarn, and prints a ball diameter of 20 ± 2 mm. amazon.co.uk shows 3.4 from 3 ratings. Two saved texts, both from the United Kingdom, describe a weekly machine wash in a mesh bag and fine debris caught in a smaller pool filter and in aquarium filters, without shedding in those filters. The third rating has no text in the file, so the reason for the 3.4 is not written down. The bullet says reusable and does not say washing machine, and it does not say a mesh bag is in the box. Hot-tub use is claimed in a bullet and still listed as a question. The parcel dimensions are printed as 1 × 1 × 1 cm, which does not describe a 200 g bag of balls.
Pros
Cons
Best for: You are trying a very small filter or an aquarium, and you can return the bag if the missing rating matches a fault you cannot accept.
Less suitable: You need a published gram table for an SX or Bestway pump, or a star line built on more than three ratings.
Specifications
Common questions
How much sand does the listing say 200 g replaces?
The bullet says 200 g of these balls is equivalent to 4 kg of filter sand. That is the seller’s line, not a fill taken from an Intex or Bestway table.
What are they made of?
The bullet names acrylic, polypropylene, and polyester yarn, and prints a ball diameter of 20 ± 2 mm.
Does the listing say they suit a hot tub?
The bullet says they can be used in hot tubs. The page still lists hot-tub use as a question.
The Rakiuty listing at £3.99 puts 300 g in the title, 200 g in a parameter bullet, and 310 g on the technical line. The title says 300 g is equivalent to 4 kg of filter sand, which is the same 4 kg slogan as the 200 g Rakiuty bag. The bullet names acrylic, polypropylene, and polyester yarn and a diameter of 20 ± 2 mm, and the process figures copy the other Rakiuty page, including a density printed as 1.38 g/cm rather than g/cm³. The file has no star rating and no review text. Install method, whether any filter pump is suitable, and how often to replace them are questions on the page with no answers. The parcel line is again 1 × 1 × 1 cm. First available is 27 March 2026, so the page is new and still does not say which of the three weights arrived.
Pros
Cons
Best for: You are only checking whether this ASIN is the same product as the 200 g Rakiuty before you order.
Less suitable: You need a known pack weight, a wash instruction, or any customer record.
Specifications
Common questions
How much is in the pack?
The title says 300 g. A parameter bullet says weight 200 g. The technical details line says 310 g. The file does not say which figure was weighed.
Will they fit any filter pump?
That question is on the page and is not answered. The bullet names swimming pools, filter pumps, aquariums, and hot tubs without a model list.
How often do they need replacing?
The page asks the question and does not answer it. No customer-review line is in the file.
Seven amazon.co.uk listings were scored on 19 October 2026 from the prices and star lines on those pages and the UK review notes saved with them. This is not a laboratory filtration test. A sand-replacement slogan, a micron line and a star rating are what the listing states. None of them is a measured result, and none of them is a PWTAG approval. The highest score is the top pick. Best value is the £9.99 pack whose title weight converts to within 5 per cent of the technical line, with a wash line on the listing and at least four UK review texts. The cheaper £3.99 bag is not best value, because the star line is 3.4 from 3. The four weights below sum to 100.
Amazon evidence
40%Up to 40 points. Stars contribute a share of 24, then a band for the review count on that line. A missing star line scores 0. The Intex line is 4.5 from 1,004. A 5.0 from five reviews does not outrank that file.
Listing fit
30%Up to 30 points when the title weight and the technical weight agree, a polymer is named, a wash method is printed on the listing, the sand claim does not contradict itself, and the model is one a pump maker publishes a fill table for. A doubled weight, or three different weights on one page, scores 0 on the weight line.
Review outcome
15%Up to 15 points from the UK review texts against the star line. A short file with no repeated fault sits in the middle. A star line under 4.0 with fewer than 10 reviews stays low even when the saved texts are positive. No review text scores less. No rating line scores 0. None of these files had a repeated functional fault in the UK texts.
Value
15%Up to 15 points for the shelf price in GBP against agreeing weights, a wash line and the review file. The lowest price alone is not best value. The £9.99 Bomxmon pack leads this criterion. The £3.99 bag with three weights and no reviews is at the bottom.
Filter balls in this comparison are a sand-tank fill for a seasonal or above-ground pool, not a cartridge and not a disinfectant. On these seven amazon.co.uk listings the shelf runs from about £3.99 to about £13.99. Start with the pump manual, then a published gram table, then whether the title weight and the technical weight agree. A micron slogan and a star line are what the page states. They are not a lab result.
Pool filter balls are loose polyester or polyethylene fibre spheres that sit in a sand-filter tank in place of graded silica sand. In the UK they are bought mainly for above-ground and seasonal pools. The practical advantage is weight: a few hundred grams of balls instead of a 10–25 kg bag of sand. Cartridge nets, spa cartridges and pond wool are different housings. Filter glass is the other sand alternative, and it is still a granular bed. Balls do not disinfect the pool.
Intex, Bestway, Filterlogic and these generic bags do not share one sand-replacement figure. A 500 g Intex bag is not the fill for every SX pump, and 28 g of Polysphere per 1 kg of sand is not a licence to copy the sand’s kilogram weight.
Bestway and Steinbach say hand wash. Intex allows a washing machine. No fabric conditioner, and do not tumble-dry balls that say not to. A review method is not the same as a wash line printed on the listing.
Balls do not disinfect, and they do not remove the need to see the bottom. The 3–5 micron line is a seller bullet. Leaving old sand underneath, or assuming the balls fit every filter, is a separate fault from the water chemistry.
The first check is the filter manual. Use balls only if that pump, or that ball brand, says so. A Lacron-style vessel that names sand only is a no, and Intex fibre balls are not a cartridge or a spa-cartridge replacement. The second check is a published gram table, not a rival slogan on the bag you happen to be holding.
A wash method counts when it is printed on the listing, not only in a review. Intex allows backwash, a tap rinse or a washing machine. Bestway and Steinbach say hand wash and do not treat backwash as the cleaning method. No fabric conditioner. Do not tumble-dry balls that say not to. On these pages, machine wash is on the Intex bullets, a hand scrub or machine wash is on yunwailc, and a laundry-bag wash is on STEEIRO. Bomxmon says washable.
Three typical situations, each with a recommendation from this comparison.
You have an Intex sand pump whose published table calls for about 500 g, and you will wash the balls the way Intex prints. Intex 29045 is about £10.99, model 29045, with 4.5 from 1,004 reviews. Ten of 50 saved texts are UK, and the catalogue field says Glass.
You accept a thin review file on a small seasonal pool and you want the heaviest generic bag in this set. STEEIRO is about £13.99, with a title of 1,800 g against 1.82 kg, and 5.0 from 5. The only saved UK text is a paddling pool, and the title says blue and white.
You want a generic bag around 700 g and you will check the fill against your pump manual rather than a sand slogan. Bomxmon is about £9.99. The title is 1.54 lb against a 720 g technical line, the listing says washable, and four UK texts sit under 4.8 from 5.
The top pick is Intex fiber balls, 500 g (29045), at about £10.99. It has the highest score in this set: model 29045, a 500 g title against 510 g, machine wash on the bullets, and 4.5 from 1,004 reviews. Ten of 50 saved texts are UK, and the catalogue material says Glass. The best value is Bomxmon at about £9.99, because 1.54 lb converts to within 5 per cent of 720 g, the listing says washable, and four UK texts are saved. It is not the top pick: five reviews, and the polymer is not named. The £3.99 Rakiuty bag at 3.4 from 3 is not best value. None of these scores is a lab test or a PWTAG approval.
Bomxmon filter balls, 1.54 lb
About £9.99, with 1.54 lb within 5 per cent of 720 g, a wash line on the listing, and four UK texts under 4.8 from 5.
Editorial
Peter F. is the editor for DIY & tools at productscompared.co.uk. Comparisons in this category are checked against amazon.co.uk listings, review evidence and public UK sources.
Guides on what to look for, how to use a product, and common mistakes.
Public UK sources for pool filtration, taken from the research digest. Listing prices, stars and review counts are from amazon.co.uk on 19 October 2026.
This page contains affiliate links to amazon.co.uk with the tag pcuk26-21. If you buy through them, we may earn a commission at no extra cost to you. Prices, stars and review counts are the UK listing lines checked on 19 October 2026. We did not run a lab test.
