How to Clean a Hot Tub Filter Cartridge

Keeping that water clear and disease free is essential part of care and maintenance for our Hot Tubs. The Filter cartridge is a key element of this. The filter will trap all the small debris that is too small to be caught in the basket but large enough to make our water look murky and unappealing. In this post, we’ll look at a step-by-step guide on how to clean a filter cartridge. 

For clean and functioning filters, there are three time periods to remember: 2-3 weeks, 2-3 months, and once a year. If you follow these short instructions for each of these periods, your filter and hot tub will stay clean and last longer.

2-3 Weeks: A Quick Rinse and Inspection.

While doing your regular inspection of your hot tub, you should remove your filter from the pool and rinse it with a garden hose to release larger debris such as hair and leaves. This is a quick process just to keep your filter functional between more serious cleanings.

2-3 Months: Thorough Cleaning

This is the time when you’ll want to remove the filter and perform a more thorough cleaning. We recommend keeping a clean filter on hand to replace with your dirty one. This extends the life of both filters as well as allows you to use your hot tub without waiting a day.

Once a Year: Replace Your Filter

Filters are only made to last for about a year, more or less depending on use. We don’t recommend using your filter for more than 12 months though as the filter can become ineffective and leave debris and bacteria in your hot tub water. If you’re using two separate filters which you are alternating, you can obviously use both for longer, but try to keep track of how long you’ve had your filters and how many months they’ve been in use. When they reach 12 months, you should replace.

Step-By-Step Guide

The first thing that you are going to have to do is remove the filter cartridge from the housing or filter body. Normally, depending on the brand, there will be a fastener at the bottom that needs to be removed before the lid can be pulled off to reveal the filter. This can be quite tight. I know with my tub I am limited with space so I actually remove the whole of the filter and housing body when I do a cartridge clean.

Once you have the top off the body, you can access the filter cartridge. Look how manky and dirty this one is!

The next thing that you want to do is hose the heavy dirt off. I tend to sit mine in a bucket whilst I do this, makes getting rid of the dirty water a little easier.

Once you have rinsed off the filter, you are going to want to let it sit in cartridge cleaner for 8-12 hours. This kills all the bacteria that can build up in the filter. It also breaks down the oils and greases that also build up on the filter cartridge.

If like me, your bucket is not big enough to immerse the whole filter, you are going to have to flip it over after the first 8-12 hours of soaking.

This point is also a good time to give the “o” rings and the filter housing a good clean with the hosepipe too.

Once all rinsed off, you are ready to reassemble and put the filter back to work keeping that water lovely and clear!

Hope you have found this helpful!

Can I Help You?

If I can help you in any way I would love to hear from you. You can get in touch using the form below.

Thanks - Andi


Hi, Andi here. I own and also write all of the articles and info pages on the site. Some years back now, I built my own hot tub but struggled to find the information I needed. So, once my tub was complete, I started this website to help others in their own pursuit of hot tub and plunge pools DIY building information.

Today, I've helped over 1000 DIY customers just like you all over the world build hot tubs and pools. Have a good look around the site, there are lots of resources here. Please do get in touch if I can help you. - Cheers, Andi

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