How to clean a hot tub filter to keep it in great working order

Wondering how to clean a hot tub filter correctly? Many long-time hot tub users will know how important this is, but if you've just bought a hot tub, you'll need to know all about how to keep it and all of its parts clean and functional. 

Hot tubs are one of the best garden furniture pieces that you can invest in. Fun and luxurious, they can transform your outdoor space into a relaxing spa experience and provide a fantastic focal point in your garden. 

But in order to keep the water in your hot tub sparkling clean for everyone to enjoy, it’s important to regularly clean the hot tub filter.

If you’re new to hot tub ownership, this might sound like a tricky task. Well, we’ve gathered some advice from the experts in order to break it down for you; here are their top tricks and tips.

How to clean a hot tub filter - what you'll need

• A garden hose, tap, or in a bucket of clean water
• A hot tub cleaning solution like ClearWater Filter Cartridge Cleaner from Amazon
• Or a mild laundry detergent; we like Ecover’s Delicate Laundry Liquid, available at Amazon

How to clean a hot tub filter - a step by step guide

Cleaning a hot tub filter is pretty straightforward, but the way you remove it will vary a little bit depending on the make and model of your hot tub. Thankfully, the guys over at Lay-Z-Spa have lots of helpful tips that we’ve included for you here.

They’ve also chatted with Adam About, who runs a YouTube channel all about hot tub maintenance; as a long-time Lay-Z-Spa hot tub user, he’s got great advice too. Combine the advice from our experts with the guidance in your hot tub owner’s manual, and you’ll have all the info you need to be able to give your hot tub filter a really thorough clean.

1. Turn off your hot tub

On a weekly basis, start by turning off the hot tub to prevent water from circulating. If you want to do a thorough clean of your hot tub, you could drain the old water out too, but this isn’t always necessary if it’s just the filter that you want to clean.

2. Remove the filter

Then, carefully remove the filter. Always do this by following the manufacturer's instructions. You can check out several YouTube videos, including Adam’s, about how to do this too in case you no longer have the manual (we’ve all thrown out a useful manual that we really should have kept at least once in our lives, right?!)

3. Rinse the filter under water

Under a garden hose, tap, or in a bucket of clean water, gently rinse any loose debris from the filter pleats, using your fingers to gently scrub, avoiding damaging the delicate filter material. Adam advises using a cleaning solution for this, although it’s not necessary every time.

4. Make sure the filter is in good working condition

After rinsing, it’s a good idea to inspect the filter for any tears, rips or damage that could allow contaminants to accidentally slip through the filter. If you notice any problems, it’s time to replace your filter straightaway.

5. Leave to airdry

Lay-Z-Spa advise that this step is important, as it’s a good idea to leave the filter out to air dry so that there’s no chance of mould spores growing in between the paper pleats of the filter. If once you’ve cleaned the filter, you want to pop it right back in and go on using your hot tub straight away, then you can skip this step.

6. Reinstall the filter

Assuming it’s still in good working order, simply reinstall the clean filter according to the hot tub manual.

In addition to a weekly filter rinse, Adam advises that your hot tub will need a deep clean once a month. For this, simply fill a bucket with hot soapy water, or you could invest in a hot tub cleaning solution. Lay-Z-Spa and Adam both recommend using the ClearWater Filter Cartridge Cleaner from Amazon, to be diluted with one litre for every 20 litres of water in the bucket. Be careful never to use any harsh chemicals, as these could damage the paper pleats inside the filter, so always check out what the manufacturer recommends.

Give the filter a pre-rinse with the tap/hose, then leave it submerged in the cleaner and let it soak overnight; Lay-Z-Spa recommends leaving it for at least 8 hours. This really helps dissolve any built-up dirt that could be lurking right inside the filter, that’s hard to reach by hand.

When time is up, simply rinse away any soapy residue, check the clean filter isn’t broken or damaged as you would with a weekly check, let it dry, and then pop it back in the hot tub. With this simple monthly deep clean, and additional hacks like adding chlorine to the water, your hot tub water will stay clean, and the filter will stay functioning like new. Adam’s channel has great advice on when, how much and why you need to be adding chlorine to hot tub water. 

What you’ll need

FAQs

Why should I clean my hot tub filter?

Even if the water looks clean, after every use, invisible pollutants like hair products, body lotions, and natural body oils can quickly build up in the water if not treated, leading to cloudy, unclean and potentially smelly water.

While showering before use is important and will help, the filter can still become dirty and clogged by these pollutants if you go too long without cleaning it. This can damage the filter beyond repair, meaning you’ll need to purchase a new one. 

According to Lay-Z-Spa: 'Poor filter care and maintenance is the number one cause of pump/heater failure so making sure that you have a clean filter and spares to hand is essential!’

How often should I clean my hot tub filter?

As recommended above, it’s a good idea to be rinsing the filter weekly with fresh water, to remove general build-up. ‘Between each use or at least every other day you should remove the filter cartridge from its filter housing and clean them. 

Every few weeks depending on the intensity of your hot tub use, old filters should be replaced with new ones (especially when they become harder and discoloured).’ (Lay-Z-Spa)