Hot Tub Maintenance & New Spa Brands

Hot Tub Filters How To Clean

Hot Tub Filters how to clean spa filters

Over the years, budget conscious individuals have tried different ways to clean a hot tub filter. The common practise for cleaning spa filters is to first remove the filter cartridge from the spa. There are usually front load and top load filters where accessing the filter may involve turning off the spa sothat it does not create suction with a filtration pump while trying to remove the filter. Each manufacturer will have their own instructions for removing the cartridge filter that should be followed.

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Hot Tub Filters - How to Clean Spa FiltersOnce the filter has been removed, it should be washed off using a garden hose. Washing off the spa filter regularly removes the larger debris such as hair, leaves, pine needles, bugs and other matter. Having a filter nozzle that provides more concentrated flow is good to get in between the pleats of the filter medium. There is a new device that is specifically made for cleaning hot tub filter cartridges which attaches directly to a garden hose and create a wide, concentrated stream of water to clean a hot tub filter more efficiently.

This hot tub filter nozzle allows for a wider stream directed at the pleats, so splash back is not an issue as it would be with a single point garden hose nozzle. Rotating the filter as it is being sprayed from top to bottom will insure that most of the contaminants will be washed off. Once the filter pleats are clean of dirt and filter-clogging debris, the filter can be replaced in the spa and the cleaning is done. It is not recommended to use a pressure washer, at the intense pressure can damage the filter paper.

Overnight Filter Cleaner

Overnight hot tub filter cleaner Spa Breeze

Overnight Filter Cleaner

Cleaning a hot tub filter monthly is a good practise. For additional cleaning, the cartridge filter can be soaked in an overnight filter cleaning solution, or it can be sprayed with a special hot tub filter spray which dissolves more dirt from the pleats and leaves them clean. Using the professional solutions will allow clogged pores on the filter paper to be opened by dissolving residue left behind from suntan lotion and other lotions or oils which don’t wash off easily with just water.

A general good practise is to hose the filter off every couple of weeks and soak the filter in an overnight cleaning solution every 2-3 months replacing the filter after about 18 months depending on use and how the water quality was maintained during that period.

A do-it-yourself solution to soaking a filter cartridge in a solution for advanced cleaning is tri-sodium phosphate (TSP) diluted with at the rate of one cup to about 5 gallons of water. Dishwasher detergents have also been used, but some of these can cause foaming in the spa if not completely washed off of the filter. Some frugal hot tub owners have tried laundry soap or other household cleaning agents, but invariably get a foaming problem when they begin to use the spa again.

Other do-it-yourselfers have tried bleach on the cartridge filter, since it seems to get them shiny white, but bleach can quickly degrade the fibrous material and reduce the filter life substantially negating any cost savings of using a proper filter cleaning method or solution. If a hot tub owner is set on using bleach, then it should be chlorine bleach diluted in water around 1:20. The filter must also be washed off thoroughly afterwards.

Some have even tried to use household vinegar to clean hot tub filters. This is more common when used in a diluted solution to clean the hot tub itself. Vinegar can lower the ph if left on the filter, so it should be rinsed off thoroughly. A good hose rinsing and an occaisional overnight filter bath should do the trick in most cases. In any case, if any other solution is used to clean the filter cartridge further, then it should be washed off again with the hose before replacing into the spa.

The use of a sequestering agent which are liquids added to the spa water that cause particulates to clump together so they are easily caught in the filter means the filter should be rinsed more often or after using such a chemical. Running a clogged filter over extended periods of time causes the spa pump to work harder to pull water through the filter medium which in turn results in higher operating costs or even an overheated or damaged pump.

More Filter Cleaning Tips

A very stubborn filter that is clogged with calcium carbonate (usually caused by running the spa at high pH levels or otherwise using water with a high mineral content) can be cleaned with a solution of 1:20 muriatic acid to water. There are commercial solutions available that utilize muriatic acid and are already pre-mixed or provide for exact dilution instructions.

Hot tub paper cartridge filters can get clogged pores over time and should be cleaned regularly for the best filtration performance. Filter cartridges come in many different sizes and shapes. Some have a center hole going all the way through and others have a screw-on connection or even a small rope or other addition to the filter. Cartridge filters are made by several different manufacturers and just like finding a compatible windshield wiper for a car, there are cross-reference guides for finding a compatible filter for a particular hot tub model.

Replace Hot Tub Filter Every Year

When searching for a replacement filter, it is a best practise to identify one of these markings or filter types commonly found on one of the end caps of the filter. These may include a Unicel reference number, Pleatco number, Filbur number or other cartridge filter manufacturer model number.

The main job of the filter, which is plumbed into the same line as the main hot tub circulation pump, is to filter particulates out of the water. Accessing the filter is different for each brand of hot tub, so it is best to check the owners manual to see how to remove and replace the spa filter on a particular hot tub model. When removing the filter from the spa, the power should be turned off. This will prevent the circulation pump from creating suction and holding the filter in, and the filter will be much easier to remove. This also prevents some dirt and contaminants from getting sucked back into the pumps as the filter is being removed.

Hot Tub Spa Tips FiltersWithout the circulation pump on, there is less danger of particles entering the hot tub circulation system when changing the filter. A best practise is to have another filter on hand. This allows for the immediate use of the spa again, and also allows time to clean the dirty filter – sometimes even overnight in a cleaning solution.

Some filters will require rotation to unthread them from the filter canister, while others should lift right out. After removing the filter, it is usually hosed down with water. Using one of the hose attachments can help get more dirt off of the filter. A comprehensive cleaning is achieved by placing the filter in an overnight cleaning solutions. This is why it is best to have 2 filters on hand. If a filter is older than one year old or looks visually degraded, it is best to replace it with a new one.

Save Money By Replacing Your Filter

Running a filter longer than its useful life may increase electricity costs, cause the pump to work harder and not clean the water as well. Eventually impurities can get through a worn filter as small holes start to form in the filter paper and gradually get larger. As particulates pass through the filter area and move into the hot tub circulation pump or two speed pump that provides for hot tub circulation, damage may occur to pump seals which can cause a pump to start leaking. Other damage can also be caused to the spa pump and surrounding plumbing by allowing non-filtered water to circulate freely.

Finally, after about 18 months it is best to just replace the filter even if it looks decently clean to the eye, as on a microscopic level, the pores are no longer at their optimum performance either filled with microscopic oil sediment, or are becoming larger which can allow for the passage of larger particulates. Always follow your manufacturers instructions on how to replace and clean cartridge filters.

Unkept hot tub water is one of the main causes of component failure in a hot tub, so keeping the filter clean and serviceable is an important step in keeping a hot tub running smoothly and avoiding a visit by a spa repair technician.