What is Hot Tub Clarifier? And Why Use It?

A water clarifier can play a useful role in restoring the appearance of cloudy water. It is helpful for every hot tub or swim spa owner to understand its role, and the reasons why cloudy water appears in the first place, so we’re going to cover those points here.

Hot Tub Clarifier is an additive for water that can aid the removal of routinely-present pollutants, such as algae, skin, urine, etc. It does not replace a primary sanitiser but it can help to filter out minute pollutant particles that commonly slip through the tub filtration system.

Some water clarity issues are caused by poor water management and, in particular, low sanitiser levels (chlorine or bromine). Daily water testing is very important in ensuring the correct sanitiser levels are maintained as is weekly shock dosing.

In order to understand how it works with other water treatment chemicals, let’s examine its role within the water care process.

How does hot tub clarifier work?

There are a number of hot tub water clarifiers, the most common are either is made up of polymers or natural products, such as Chitosan, that will either form a chemical bond or ‘clump’ the very small pollutant particles. These particles will inevitably be found in every hot tub, irrespective of how well the water is tested and how clean the bathers are.

In some cases the water can look dull due to minute particles not being trapped by the filters, Water Clarifier will ‘clump’ together these smaller particles to form a larger particle which in turn will be trapped in the filter.

Very small particles can easily pass straight through the filter, this is not necessarily due to poor filtration however do check the age of the cartridge filter as then often need to be replaced every 18 months or so.

Cloudy hot tub water is often caused by tiny polluting elements that continue to circulate freely through the hot tub filtration system and back into the main tank.

The continuous removal of pollutant particles is the primary reason why you should leave your hot tub filtration system running at all times, as this process will help keep your water safe for your bathers as well as looking better from an aesthetic perspective.

Another method to restore clarity is to employ enzymes. This method is being used more frequently and offers additional benefits, such as the removal of oils and fats produced by the bather which in turn place a greater demand on the sanitiser (free chlorine or bromine). We will look at the role of enzymes in a separate blog at a later date.

When to add water clarifier to your hot tub or swim spa

There are two trains of thought when adding water clarifier which are:

1. On a proactive weekly basis – Many hot tub users have found a proactive approach to clear water is to apply weekly (around 15 – 20ml per week) rather than wait until the water has gone cloudy.
2. On a reactive basis – only when cloudy water appears.

If your hot tub or swim spa is used regularly, i.e. over and above twice a week, you may find that option one is preferable due to the reduced downtime should a clarity problem occur. ‘Prevention is better than cure’ in this instance.

Ensure your hot tub water is circulating when adding water clarifier as this will distribute it evenly.

What are the alternatives to a water clarifier?

An alternative method to restore water clarity is to employ enzymes. This method is now being used more commonly and offers additional benefits, such as the removal of oils and fats produced by the bather which in turn demands a greater work load from the sanitiser (chlorine or bromine); we will cover enzymes and how they work in a separate post at a later date.

Further tips

• Ensure cartridge filters are regular cleaned (weekly). Using a hot tub clarifier on a regular basis will ensure the water is clear and inviting for your bathers, but filter cleanliness is equally important.
• Water clarifier works reasonably quickly, but if a problem persists with water clarity don’t simply continue to add the product. If clarity issues persists then the cause will be something else; see our next point…
• Hot tub water doesn’t last for ever. Typically the water should be drained and replaced every 3 – 4 months however this can be sooner if the water is either neglected or heavily used; the solution to pollution is dilution and so ultimately every hot tub and swim spa will need water to be completely replaced periodically.
• The addition of other chemicals will increase the likelihood of clarity issues. Always add chemicals in small quantities and re-test as you do so.
• Test the water daily to avoid unpleasant surprises (such as cloudy water) as these are frequently due to low sanitiser levels or a lack of shock dosing.
• Always keep chemicals safely out of reach of children and pets.