How Long Can Water Stay in an Inflatable Hot Tub?

If you’ve ever stepped into your inflatable spa and thought, “Hmm… this doesn’t smell quite like a spa day,” then it might be time for a water change. The short answer? With proper care, water can last around 3–4 months.

But that depends on how often you use it, how many people pile in, and how well you maintain the water. Think of it like milk in the fridge—the fresher you keep it, the longer it lasts.

The Key Factors That Affect Water Longevity

Chemical Balance (pH, Alkalinity, and Sanitiser)

Water chemistry is the make-or-break of hot tub care. You’ll want your pH between 7.2–7.8, alkalinity at 80–120 ppm, and a steady level of chlorine or bromine.

Get it right, and your spa stays fresh and safe. Get it wrong, and you’ll quickly run into cloudy water, itchy skin, or even damage to your tub’s inner workings.

A simple water testing kit takes out the guesswork—use it weekly and adjust as needed.

Frequency of Use and Number of Users

The more splashing, the faster the water gets dirty. A family using the tub every night will need more regular water changes than someone sneaking in a solo soak once a week.

Body oils, lotions, and even sun cream all build up. The water may look clear for a while, but trust us—it doesn’t stay “clean” forever.

Filtration and Filter Maintenance

Your filter is doing the hard graft behind the scenes. Rinse it every week, give it a deeper clean once a month, and replace it every 2–3 months.

Ignore it, and you’ll get poor circulation, murky water, and extra strain on your pump. A dirty filter is basically your spa’s equivalent of trying to breathe through a blocked nose.

The Environment and Hot Tub Cover

Where you keep your spa makes a big difference. Got trees nearby? Expect leaves and pollen. Is your garden windy? Say hello to dust and debris.

That’s why a proper cover is worth its weight in gold. It keeps out rubbish, saves heat, and even reduces evaporation. Think of it as your hot tub’s duvet.

Recognising When It’s Time for a Water Change

Visible Signs (Cloudy or Foamy Water)

If your spa looks more like a bubble bath gone wrong than a clear soak, it’s time for a reset. Foamy or cloudy water is a sure sign of oils, dirt, and dissolved solids building up.

Unpleasant Odours

A clean inflatable spa shouldn’t smell odd. If you’re hit with a musty whiff or an overpowering chemical stink, your water has had its day.

Water Chemistry Issues

Sometimes you can test and tweak until you’re blue in the face, but the numbers just won’t balance. If that happens, don’t fight it—drain it. Fresh water is the only fix.

A Step-by-Step Guide to Draining and Refilling Your Hot Tub

The Draining Process

Switch off the power and connect a hose to the drain valve. Let gravity take care of the rest. Make sure the water flows into a safe area, away from flowerbeds or delicate grass.

Cleaning the Tub

Once empty, give the liner a good scrub with a non-abrasive cleaner. Pay attention to the jets, inlets, and even the cover—these are the spots that love to trap grime.

Refilling and Rebalancing

Top up with fresh water, then grab your test kit. Balance the pH and alkalinity first, then add your sanitiser.

Let it circulate for a bit before diving in—you’ll thank yourself for the patience.

Key Takeaways

• With good maintenance, water in inflatable hot tubs lasts around 3–4 months.

• Keeping pH, alkalinity, and sanitiser levels in check is essential.

• More people and more frequent use mean more frequent water changes.

• A clean filter and a snug cover will extend water life.

• If water looks cloudy, smells odd, or won’t balance—it’s time to drain.

Conclusion

Keeping your inflatable spa fresh doesn’t need to be a chore. With regular checks, a clean filter, and the right chemical balance, you can stretch your water life and enjoy more relaxing soaks with less fuss.

At the end of the day, fresh water means a healthier, more enjoyable hot tub experience. Treat your spa well, and it’ll reward you with crystal-clear bubbles every time.