How to Maintain Hot Tubs and Spa Pools?

In this beginners guide the pool water specialists at Water Treatment Services take an in-depth look at how to maintain hot tubs and spa pools to keep them working effectively, clean and safe to use.

The guide covers lots of ground and will be useful to anyone who owns or manages a hot tub or spa either at home or as part of a business. It begins by highlighting the rules and regulations covering hot tub maintenance and safety, it then moves on to consider some of the essential tasks including how to set-up your pool, water testing and how to treat the water in your tub. It concludes with a couple of useful checklists covering essential hot tub safety, and how to handle chemicals correctly.

Beginners guide to maintaining hot tubs

When you take delivery of your first hot tub or spa pool, the prospect of managing it can appear intimidating. They are not cheap items to buy, and it’s understandable that new owners want to do the best job possible of taking care of it, keeping it nice and clean, prolonging its life, and most importantly of all, keeping it safe to use. Our straightforward beginner’s guide is designed to help you through the initial stages of hot tub ownership, setting it up correctly, and putting in place that all important maintenance plan.

What are the rules covering hot tub maintenance?

UK health and safety laws dealing with hot tub and spa water quality, testing and treatment are only applicable if you’re running a business such as a gym, hotel or leisure centre, or the pool is in a holiday property which is let to paying guests. If that’s you then you need to ensure sure that the water quality and treatment programmes you have in place are effective and meet current standards.

Although the law might not apply to domestic hot tubs, it does provide excellent guidance which it makes sense to read, understand and comply with. For more information, both the Health and Safety Executive and the Pool Water Treatment Advisory Group (PWTAG) provide excellent guidance to help hot tub owners and operators comply with health and safety law.

What are the basics of maintaining a spa pool or hot tub?

Many people refer to hot tubs as Jacuzzi’s, but this is actually a brand name. Jacuzzi was the company which first invented tubs with hydrotherapy jets back in the 1950s. Calling all hot tubs Jacuzzis is incorrect in the same way as calling all vacuum cleaners Hoovers is incorrect – but lots of people still do it. Jacuzzi is still around in the hot tub market, making high quality tubs and spa pools which have been designed to make maintenance as easy as possible.

Whatever brand of hot tub you choose to buy, you will need to maintain the water to keep it clean and safe for anyone using it. This means choosing the right chemicals and balance of chemicals depending on your skin and the way in which you’re using the tub.

How to set up your hot tub

When you use your hot tub for the first time, or start to use it again after emptying it for the winter, the general rule is to dose the water with a high level of sanitiser, at least initially. This is usually done by adding 60 grams of chlorine for every 1,500 litres of water to kick-start the sanitation process. Allow concentrations to drop to between 3 and 5 milligrams per litre before you first use the hot tub. It’s usually easier to use granules than tablets, and ensure your tub’s pump is running before adding any chemicals.

Filtration and circulation in the hot tub

Nearly all hot tubs and spa pools on the market will have a pump, and a cartridge filter system included. It is important to check that the filter is working effectively on a regular basis. If the filter in your hot tub gets clogged or dirty, then it will stop working properly and as a consequence, the water will get dirty too. Hot tub filter cartridges usually need cleaning out every week as a minimum especially if your hot tub is being used very frequently, or if you have contamination from leaves or grass falling into your tub.

How to test the water in your hot tub?

It is essential that you test your hot tub’s water regularly to make sure it is clean and safe to use. One of the easiest ways to do this is by using paper test strips. These are dipped into a sample taken from the water, and will give results about pH levels, sanitiser and alkalinity within seconds. The results of the tests will let you adjust the chemicals as needed.

Owners of hot tubs should be testing the water quality every day, whether you are using the spa or not. Before using test strips, always read the manufacturer’s instructions as these can vary from brand to brand.

Hot tubs and spas typically contain lower volumes of water and operate at higher temperatures than swimming pools. These factors can increase the potential for bacterial growth in the water, including E. coli, pseudomonas, coliforms, Legionella bacteria and other potentially nasty bugs. While microbial testing of privately operated hot tubs is at the owner’s discretion, it is highly recommended.

Pool Water Testing

How to treat the water in your hot tub?

There are several steps involved in maintaining the quality of your tub’s water.

Hot tub sanitisers

The most commonly-used chemicals for sanitising a hot tub are bromine and chlorine. Granules are usually recommended for adding to tub water, and the levels you are looking for are typically between 3 and 5 parts per million for free chlorine, and between 4 and 6 parts per million for bromine. The rate at which your hot tub consumes bromine or chlorine will depend on usage and environmental conditions, which regularly change. This is why it is important to check the levels every day.

Balancing hot tub water

Most of us will remember pH testing from school science lessons. The pH scale runs from 0 to 14, with 7 in the centre of the scale being neutral. Numbers lower than 7 mean the water is acidic, any number over 7 means the water is alkaline.

The ideal level of pH in your hot tub if you are using bromine for sanitation, is between 7 and 7.4. If on the other hand you are using chlorine, you are looking for a pH level between 7.2 and 7.6. Getting the right level of pH for your pool is essential for protecting the mechanical components of the spa (pumps, filters, jets etc.). If the pH level is incorrect, it is usually easily solved by dosing extra chlorine or bromine as required.

Monitoring the Total Hardness (TH) and Total Alkalinity (TA) is also an essential task to get right. High levels of scale within a hot tub can be caused when the waters alkalinity levels are too high. You can raise or lower alkalinity levels by dosing chemicals into the hot tub water.

If you have repeated issues with scale in your hot tub, then it might be worth considering the regular use of an anti-scale product which will prevent its build-up so that the hardness in the water won’t damage susceptible components of the tub.

How to stop foaming in your hot tub?

The most common cause of foaming in hot tub water is detergent residue left on swimming costumes after laundering. Wherever possible, it’s a good idea to ask anyone using the hot tub to take a shower with their costume on before getting into the water. This will help rinse any detergent off the clothing, but will also get rid of any oils, greases, lotions or make-up residues on the body. If you already have foam build-up in your tub, then there are special anti-foam chemicals you can use to remove, and then prevent it.

How to clean your hot tub?

Waterline grease which forms on the surfaces of the hot tub itself is easily removed during periodic cleaning, and this step will also mean that the chemicals you add to your spa will work properly too. Don’t be tempted to use household cleaning products designed to be used in your kitchen or bathroom; you need a specific spa cleaning product which won’t affect the pH levels, cause foaming or damage the surfaces of the tub.

How to drain the water from a hot tub?

The water used in a hot tub will, over time, absorb chemicals, minerals and other materials. These are known as Total Dissolved Solids, or TDS. The TDS levels in the water can stop hot tub treatment chemicals from working as they should to keep the water clean and safe to use. PWTAG recommend that the water should be changed monthly, but if your pool is used only very infrequently, every 3 to 4 months might be sufficient. At the same time as draining your tub, take the opportunity to clean and flush the pipes through using a special pipe cleaning chemical mix.

Checklist for hot tub safety

The following checklist can be very useful for ensuring your hot tub is used safely.

Always check the water temperature – the temperature should never go above 40 ^oC, less if children will be using the pool.
Never leave children, or others who cannot swim, unattended in any sort of pool, including hot tubs.
Stick to the manufacturer’s recommendations regarding maximum pool capacity.
Never run any electrical appliances in or near your hot tub.
Keep articles made of glass away from the tub at all times.
Don’t drink alcohol immediately before using a hot tub, or while you are in the water.
Speak to your doctor before using a hot tub if you have cardiovascular problems, have high blood pressure, or are pregnant.
Follow the manufacturer’s recommendations regarding water quality and pool maintenance.
Always wear suitable personal protective equipment (PPE) including suitable gloves when using chemicals to clean or dose the pool, or change filter cartridges.
Regularly test the water for bacteria, especially the potentially deadly Legionella bacteria.
If you are a business, further information can be obtained from both the Health and Safety Executive and PWTAG who provide excellent guidance to help hot tub owners and operators comply with health and safety law.

Guidance for handling hot tub chemicals

As well as the general safety rules, there is also more specific guidance about how to safely handle chemicals when treating your hot tub.

Always wear suitable protective equipment.
Always read and follow the manufacturer’s instructions before starting to use any chemicals.
If pre-dissolving hot tub chemicals, always put the chemicals into the hot tub water rather than the other way around.
Never mix chemicals.
Use a clean, plastic container when dissolving chemicals.
Dissolve the chemicals in a well-ventilated area, or outside.
Take care to avoid any chemical spills wherever possible. If chemicals are spilled, clean them up right away. Clean away any spillage with clean water.
Don’t use chemicals without labels.
Wash your hands thoroughly after using hot tub chemicals.
If you are a business, further information can be obtained from the Health and Safety Executive and PWTAG on how to comply with health and safety law.

Expert pool water testing solutions

Water Treatment Services offer a comprehensive range of water quality testing and laboratory analysis solutions to support owners and operators of swimming pools, spas and hot tubs. Our experts can provide advice and support to help you identify the most appropriate strategies for the on-going management of your pool facilities to keep them safe and in tip-top condition.

With offices in London serving the South and South East England, Manchester (North West), Birmingham (Midlands), Bristol (South East England and Wales), Leeds (North and North East) and Glasgow (Scotland), supported by regional teams of specially trained technicians, in-field specialists and consultants we can offer professional, cost effective water management and laboratory analysis solutions across the whole of the UK and internationally.

Contact us today to learn how our expert water management solutions can help keep your hot tubs and spa pools clean and safe to use.