How to Clean a Hot Tub Filter

Keeping your hot tub clean is not just a way to ensure an enjoyable bathing experience, it is also important for ongoing maintenance and to keep your spa running smoothly. One of the key aspects of keeping a hot tub clean is looking after your hot tub filter with regular cleaning and periodic replacement. Keeping a spa filter clean can have benefits that you may have not assumed including better efficiency, using less chemicals and increasing jet power! This blog post will help you understand what a hot tub filter is, what it does, why it is important to keep it clean, how to clean a filter and some useful tips and advice. 

What is a Hot Tub Filter? How Does it Work? 

A hot tub is designed to filtrate and heat through circulation. Dirty water passes through the filter and/or suctions using the pump or circulation pump then goes through the heater and is pumped back out through the jets. This process of circulation ensures clean and warm water, as well as hydrotherapy - the whole basis of a hot tub. The filter plays a key role in this process as it is ensures that the water going back through the pump and heater is clean and free of debris, it is also stage 1 in the circulation process meaning that any sort of issue here will cause issues further down the line. Issues with dirty filters will be explained below. 

Hot Tub Filters are usually made of a pleated, polyester media. This media filters the water and catches debris on it's way through. Manufacturers have used innovation to improve filter material over time. One example is the patented Hot Spring Tr-X filter, which is made of ceramic fibre making it more durable, longer-lasting and more efficient. 

Why is it Important to Keep a Hot Tub Filter Clean?

As outlined above, a hot tub filter is fundamental to the workings of a hot tub and if dirty it can cause the following issues:

  • Low Flow - this can be highlighted by an error message on the screen such as "---" or "FLO" or "DRY". This is where the sensors are not sensing enough flow through the heater so the heater is cut off for safety. Low flow can also cause strain on the pump, slower heating and less power coming through the jets.
  • Dirty water. The filter plays a key part alongside your sanitiser (chlorine or bromine) to keep your hot tub clean. When a filter is clogged or dirty then it can disrupt water clarity, cleanliness and also cause inefficient sanitisation (using lots of chlorine or bromine). 
  • Strain on parts. If a filter is extremely dirty then debris can make its way into the heater, pumps, sensors and other key working parts of the hot tub. This can cause parts to become faulty.

How Long Should Hot Tub Filters Last? 

Hot Tub Filters should last a minimum of 1 year and generally speaking a maximum of 2 years. If a filter is maintained and cleaned regularly then it will last longer. Ceramic hot tub filters like the Tr-X filters from Hot Spring can last up to 5 years due to the durability that the ceramic design brings. A hot tub filter needs replacing when the media material starts to break up. At this point the filtration is becoming ineffective and a fresh filter will help save money on efficiency, protect the working parts of your hot tub and help with improved flow. A good way to make hot tub filters last longer is to have a spare and swap filters regularly to allow time for thorough cleaning and consistent filtration. See our range of high quality replacement filters.

How to Clean Hot Tub Filters

Option 1 - Quick Rinse

This option is the quickest way to clean your filter and is recommended as a weekly process. It is not a deep clean but rather a quick rinse to remove large debris. This will not remove any grease or oil from your filter so is not reccomended for a heavily soiled filter. If you filter is heavily soiled, see option 2 or 3. To make rinsing your filter easier and more thorough, check out our Super Blaster Filter Cleaning Tool.

  1. Turn off your hot tub at the isolator switch.
  2. Remove your filter.
  3. Use your hose to rinse up and down and inside the pleats.
  4. If you have time, allow your filter to dry before placing it back into your spa. 

Option 2 - Instant Filter Cleaner Spray

A more thorough option than just a quick rinse and recommended as a monthly or fortnightly process depending on hot tub usage. Instant Filter Cleaner is a great degreaser and will remove oils from your filter. At Happy Hot Tubs we recommend this option as the best and most efficient method to clean your filters.

  1. Turn off your hot tub at the isolator switch.
  2. Remove your filter.
  3. Give your filter a quick rinse to remove large debris.
  4. Spray the surface of the filter with Happy Hot Tubs Instant Filter Cleaner thoroughly to impregnate the filter, wear protective clothing (Gloves and eye protection etc.)
  5. Allow the filter to stand for 10 to 15 minutes
  6. The gentle use of a Soft Brush or Happy Hot Tubs Super Blaster can help lift contaminents.
  7. Heavily soiled filters may need a second treatment or soak treatment.
  8. Rinse thoroughly before returning the filter to your spa. If you do not rinse thoroughly, you will experience foaming. 
  9. If you have time, allow your filter to dry before placing it back into your spa. 

Option 3 - Filter Soak

This option is the slowest cleaning process as you use a degreasing solution to soak into the pleats of the filter over a period of time. As the process is slower, it ties in nicely with your water drain and refill every 3-4 months. Some hot tubbers will follow this process monthly as they swap in a clean & dry filter and therefore have time to allow the dirty filter to soak and clean. 

  1. Turn off your hot tub at the isolator switch.
  2. Remove your filter.
  3. Give your filter a quick rinse to remove large debris.
  4. Place a filter soak solution such as Happy Filter Cleaner, Immerse Filter Cleaner or AquaSparkle Cartridge Cleaner in a bucket as per the correct dosing on the bottle. 
  5. Leave the filter to soak for a minimum of 8 hours.
  6. Rinse thoroughly before returning the filter to your spa. If you do not rinse thoroughly, you will experience foaming. 
  7. If you have time, allow your filter to dry before placing it back into your spa. 

FAQs

Can I use my dishwasher to clean my hot tub filters?

For normal polyester woven filters, you cannot use your dishwasher as this can damage the media. If you have Hot Spring Tri-X Ceramic Filters, then you can rinse your filters in the dishwasher on a basic rinse cycle. 

Why is it best to dry a hot tub filter before putting it back in?

By drying a filter, you reset the fibres and make the filter more effective. It is fine to put a filter in wet or dry but dry tends to offer more effective filtration for a period. 

Can I run my hot tub with no filter in?

No. If you do this, you add the risk that debris and other items could go down into the pipework and cause damage to your hot tub. It is best practice to turn your hot tub off when removing your filter.

How often should I clean my hot tub filter?

This depends on usage but you should visually check your hot tub filter at least weekly. If you feel it needs rinsing then at this point you should give it a quick rinse with the hose. You should give your filter a more thorough clean monthly. 

How often should you replace a hot tub filter?

A standard paper hot tub filter can last up to 2 years if it is cleaned regularly. Hot Spring Tri-X Filters can last up to 5 years.