When to replace or clean a hot tub filter

Last reviewed November 1, 2026

There is no single replacement date. Jacuzzi says 12–24 months for a pleated cartridge. Hot Spring’s filter article says 2–3 years for a polyester cartridge and 4–6 years for TRI-X, while its maintenance page says every three years. Sundance’s 2024 manuals use 12 months and 4 months on the 680 Series and 3 months, or earlier, on the 780 Series disposable cartridge. Unicel gives no end date. Cleaning varies too: Jacuzzi’s regular-use deep clean is 4–6 weeks, Hot Spring’s rinse is monthly, and Pleatco’s note on most spa makers is monthly or every two weeks with heavy use. The calculator counts those published figures from a date you enter. Where the sources do not match, it shows the range and says so.

Unicel’s maintenance page and Jacuzzi’s filter page both say to keep a second set, so one cartridge can be cleaned while the other is in the spa. A spare is what those pages describe. It is not a sale. The dates on this page are calendar readings of published intervals.

What the sources print

Read across a row. Do not read down the Replace column as one cartridge’s range. The 3-month figure is a Sundance 780 disposable cartridge. The 4–6 year figure is a Hot Spring TRI-X cartridge. Those are different products.

Source	Cartridge	Clean	Replace
Jacuzzi: Hot Tub Filter Cleaning Made Easy	Pleated cartridges	Regular family use: rinse every 7 days, deep clean every 4–6 weeks. Heavy use (4–6 bathers several evenings a week, a rental or Airbnb amenity, or frequent sunscreen and cosmetics): consider a rinse every 2–3 days and a deep clean every 3–4 weeks. Light or seasonal use (winter-only, 1–2 people): rinsing every 2 weeks and a deep clean every 6–8 weeks may be sufficient.	Every 12–24 months, or sooner if the fibers are torn, flattened, or heavily stained. One page gives that range. It does not print a shorter replacement calendar for heavy use.
Hot Spring Spas: How Do Hot Tub Filters Work?	Polyester (“paper”) cartridge	Rinse with a garden hose every month. Soak the filters every time you drain the tub. The article says the schedule varies with use, and the month it prints is still “every month.”	Every 2–3 years, depending on usage and visible wear.
Hot Spring Spas: How Do Hot Tub Filters Work?	TRI-X cartridge	Same as the polyester row on that page: a monthly hose rinse, and a soak every time you drain.	Every 4–6 years, depending on usage and visible wear.
Hot Spring Spas: Maintenance Tips	Filters (the page does not name TRI-X)	A light clean each month: hose the pleats, and use a filter cleaner.	Every three years, with genuine Watkins replacement filters.
Sundance Spas 680 Series Owner’s Manual (2024)	680 Series pleated MicroClean Mini filter	Clean the pleated filter monthly. The manual calls for a high-pressure hose nozzle on that outer filter.	12 months.
Sundance Spas 680 Series Owner’s Manual (2024)	680 Series MicroClean Mini insert	No chemicals, and a low-pressure rinse. Not a degreasing-soak schedule.	Every 4 months.
Sundance Spas 780 Series Owner’s Manual (2024)	780 Series small disposable MicroClean cartridge	The monthly clean in the 680 and 780 manuals is for the pleated filter, a different piece. Sundance says not to use filter cleaners on the inner inserts.	Every 3 months, or earlier.
Unicel: Maintenance & FAQ	Spa cartridges	Set a routine from how much the spa is used. No week or month count for spas. The 8 psi gauge mark on this page is for swimming pools, not a spa calendar.	No defined end date. Replace when cleanings get closer together, flow stays low and differential pressure stays high, or the media tears or the center core collapses.
Pleatco FilterWash information sheet	What Pleatco says most spa makers recommend	Monthly, every two weeks with heavy use, and after a party. Pleatco does not print a separate light-use gap.	Not a replacement interval. This sheet is about cleaning.
CDC: Controlling Legionella in Hot Tubs	Hot tubs, in CDC’s Legionella module	Not a week-by-week home cleaning calendar.	Replace cartridges according to the manufacturer. No month count of CDC’s own.

For a Hot Spring polyester cartridge, the article’s 2–3 years and the maintenance page’s three years are different sentences. The three-year figure sits at the end of the 2–3 year range. For TRI-X, the article says 4–6 years and the maintenance page says three years without naming TRI-X. Read together, those Hot Spring sentences run from three years to six years, and they do not agree.

Count it from a date

Pick the cartridge the source is talking about. The use levels are Jacuzzi’s and, for heavy use, Pleatco’s. A maker that did not print a separate light or heavy number does not get one here. Nothing you type into the dates is sent anywhere. The reminder form further down is the only part of this page that stores anything, and only if you submit it.

The form stores a request. It does not send email, and it is not a newsletter or a series of updates. The interval list is the list the form can store. It is not a promise that your manual uses one of those choices. The note under the dates says when a published interval is missing from that list.

When you have the part number, open the replacement schedule and reorder page. It keeps these intervals, attaches them to one cartridge already in the dataset, and lists that cartridge’s buy link. The cross-reference lookup lists every equivalent without the schedule. This page does not print a price. The longer write-ups are how often to replace a hot tub filter, how often to clean a hot tub filter, and how to clean one.

Questions

How often should I replace a hot tub filter?

There is no single interval. Jacuzzi says every 12–24 months for a pleated cartridge. Hot Spring’s filter article says every 2–3 years for a polyester cartridge and every 4–6 years for a TRI-X cartridge, and its maintenance page says every three years. Sundance’s 2024 680 Series manual uses 12 months for the pleated MicroClean Mini filter and 4 months for the insert. The 780 Series manual says every 3 months, or earlier, for the small disposable MicroClean cartridge. Unicel says a cartridge has no defined end date.

How often should I clean it?

That also varies. Jacuzzi’s baseline for a regularly used family tub is a rinse every 7 days and a deep clean every 4–6 weeks, with a shorter interval for heavy use and a longer one for light use. Hot Spring says a monthly rinse and a soak when you drain. Pleatco says most spa makers recommend monthly, every two weeks with heavy use, and after a party. Unicel tells spa owners to set a routine from how much the spa is used and does not print a week count for spas. The calculator shows the range when those sources do not say the same thing.

Will the reminder form email me or add me to a newsletter?

No. The form stores the request and does not send email. It is not a newsletter and it does not sign you up for regular updates. The only address for a deletion request is [email protected].

What if my spa’s manual is not in the list?

Follow that manual. CDC’s hot-tub module on Legionella says to replace cartridges according to the manufacturer. The calculator only dates the intervals published by the sources named on this page.

Sources

This page summarizes published manufacturer and public-health guidance. Follow your own spa’s owner’s manual when it differs. See the disclaimer. A correction goes to contact, which reaches [email protected] and no other address. The method is on the about page.