New Hot Tub Owner FAQ: The Most Common Questions Answered

A hot tub is the perfect place to switch off and unwind. But if it’s your first one, there are a few things worth knowing — from day-to-day care to ideal temperatures and using it through winter. Here are the questions we get asked most often by new owners, with practical answers so you can enjoy your spa with zero stress.

1. How often should I change the water in my hot tub?

A hot tub is a true wellness oasis — but only if the water stays clean and fresh. On average, you should change the water every 3 to 4 months, depending on how often it’s used and how many people use it. If it gets heavy use, or regularly has a full house, plan to change it more often.

Tip: If the water turns cloudy, smells off, or develops slimy residue, it’s time for a change.

2. Which chemicals do I need for hot tub care?

The right water care keeps your hot tub hygienic and the water comfortable to sit in. The essentials are:

• Sanitiser (chlorine granules or bromine): kills bacteria and germs. For most owners we recommend chlorine, and our guide to chlorine or bromine explains why, and when bromine is the alternative.
• pH adjusters (pH Up / pH Down): keep pH between 7.2 and 7.6.
• Shock treatment: oxidises contaminants and clears the water.
• Alkalinity adjuster: stabilises pH and stops it swinging too quickly.
• Calcium hardness products: prevent corrosion and scale.

Test your water 2–3 times a week with 3-in-1 test strips, or grab everything in one go with our Starter Hot Tub Chemical Kit.

3. What temperature should my hot tub be?

Most owners set their hot tub somewhere between 37°C and 40°C (roughly 99–104°F). Within that, the ideal temperature comes down to personal preference:

• 37°C (98.6°F): a comfortable, relaxing soak.
• 39–40°C (102–104°F): great for muscle relaxation and cooler months.

Children under 12 should only use the hot tub at a maximum of 36°C, in line with BISHTA guidance, and for shorter sessions.

4. Can I use my hot tub in winter?

Yes — a hot tub is especially enjoyable in winter, but it does need a bit of extra care:

• Use a quality insulated cover to retain heat.
• Keep the temperature constant to avoid frost damage.
• If you’re not planning to use it through winter, properly winterise the hot tub by draining it fully, shutting the system down and storing it correctly.

5. How do I keep the water crystal-clear?

• Regular testing: make sure all values stay in the optimal range, and adjust your chemicals as needed.
• Shower before getting in: avoids oils, lotions and dirt entering the water.
• Filter care: rinse the filter weekly, deep-clean monthly with a filter cleaner, and replace it roughly every 6 months. Our practical guide to cleaning your hot tub filter explains each step.
• Weekly shock treatment: removes organic contaminants.

6. Can I use bath bombs or essential oils in a hot tub?

No. Bath bombs and essential oils aren’t suitable for hot tubs — they leave residue that can clog the filter and cloud the water. Use proper hot tub aromatherapy products designed for spa systems instead.

7. How many people fit in a hot tub?

The size of your tub determines comfortable capacity:

• 2–3 people: ideal for couples or smaller spaces.
• 4–6 people: perfect for families or small groups.
• 7+ people: great for sociable evenings with friends.

When choosing a hot tub, look at seating layout, comfort and the space you have available.

8. How do I drain and refill my hot tub?

1. Switch off the power.
2. Attach a garden hose to the drain valve.
3. Open the valve and let the water drain out completely.
4. Wipe down the inside, then refill with fresh water through the filter housing to prevent air locks in the pipework.
5. Switch the power back on and balance the water chemistry.

For more detail on step 3, see our guide to operating your drain valve to empty your spa.

Tip: change the water every 3–4 months to avoid build-up and keep performance at its best.

Conclusion

A hot tub gives you proper relaxation — as long as you look after it. With regular care, the right chemicals and good water quality, your spa stays hygienic and inviting. Follow these basics and you’ll get crystal-clear water, low maintenance costs and many years of enjoyable soaks.

More questions new owners ask

9. What power supply does my hot tub need?

It depends on the model. Plug and play spas, such as our 13 amp range, run from a weatherproof outdoor socket with RCD protection. Larger spas need a 32 amp hardwired supply with RCD protection, installed by a qualified electrician. Never use an extension lead.

10. How long does it take to heat up the first time?

Allow roughly 1 to 2°C an hour with the cover on. Starting from cold mains water, that usually means most of a day, and longer in winter. Our guide on how long a hot tub takes to warm up has more detail.

11. What do I need to do in the first week?

1. Fill through the filter housing and check for leaks before switching on.
2. Heat with the cover on.
3. Test the water and balance it: total alkalinity first, then pH, then sanitiser.
4. Shock the water once it is balanced.
5. Test daily for the first week while you learn how your spa behaves.

12. What are the target ranges for the water?

Test	Target
Total alkalinity	80 to 120 ppm
pH	7.2 to 7.6
Free chlorine	1.0 to 1.5 ppm

The free Canadian Spa Water Test app works out doses from your test strip readings and your spa's water volume.

13. What does the warranty cover?

Our hot tubs come with a manufacturer's warranty covering faults in parts and workmanship. It does not cover damage from wrong or overdosed chemicals, frost damage after a spa has been left off, or running the pumps without water. Check the details on our warranty page. An extended warranty is also available.

14. How does delivery work?

Standard delivery is kerbside, so plan who will help move the spa into the garden, and measure gates, paths and corners first. Our guide to hot tub delivery options explains the choices, including back garden installation.

15. Does my hot tub need servicing?

A yearly service helps catch small problems early. Our technicians can carry out a full maintenance service, a winterising service or a health check if something is not working right. See hot tub servicing for the options.

16. How long should I stay in?

Most people enjoy 15 to 20 minutes at a time. Get out sooner if you feel dizzy or too hot, and drink water. Our guide on how long to stay in a hot tub covers this in more depth.

17. Who should not use a hot tub?

You should not use a hot tub while pregnant. Anyone with a heart condition, high or low blood pressure, or who takes medication that affects these should speak to their GP first. Do not use the spa after drinking alcohol.

18. What should I keep in stock?

• Sanitiser, pH Up and pH Down, alkalinity booster and shock, or a complete chemical kit.
• Test strips.
• Filter cleaner and a spare filter set.
• A leaf skimmer net.