Buying a Hot TubMaintenanceHot Tub TipsTroubleshootingHealth + Fitness

How to Clean Mold from Your Inflatable Hot Tub

This blog post may contain affiliate links.

Inflatable hot tubs are an excellent choice in many ways. Like all hot tubs, they provide hours upon hours of relaxation, stress relief, and numerous health benefits. Moreover, they’re easy to move when needed, relatively inexpensive, and capable of being stored in a modestly sized closet when it’s time to close up shop for winter. In cold climates, more permanent hot tub installations generally require a fair amount of work to prevent them from being damaged by freezing temperatures during the cold months; this isn’t that much of an issue with inflatable models. 

However, simply draining and folding an inflatable hot tub can lead to mould growing all over your prized little hot water oasis. This is not only unsightly verging on disgusting; certain types of mould are known to cause health problems that range from irritating to serious. Even worse, many doctors will struggle to diagnose the real cause of these, treating the symptoms instead. 

If you want to prevent mould from taking over your soaking station or find out how to clean mould from an inflatable hot tub, it’s essential to understand where it comes from, what makes it grow, and how you can combat it. Fortunately, normal maintenance and regular cleaning already go a long way toward taking care of this potential problem. Read on as we discuss what to do to keep your hot tub in tip-top shape, ensuring that you and your family always have a clean and safe space to unwind after a demanding day. 

Understanding Mold and Its Causes 

What Is Mould? 

Mould is what we call a wide variety of fungi – the same family as mushrooms – that grow in damp, warm, and dark environments. It can be found in various colours, including black, green, and white. Some species are less harmful than others, but you don’t really want any of them taking up residence in your hot tub, for aesthetic reasons if nothing else. 

Where does mould come from? Mould germinates from particles we call spores instead of seeds. These spores are always present in the air we breathe; in fact, they are sometimes poisonous and can lead to several kinds of respiratory complaints. When these spores land on wet surfaces, mould growth is almost certainly going to happen unless you’ve taken steps to prevent it. Mould spores can also be introduced into a hot tub by bathers themselves, either hitching a ride on their skin or through lotions, soaps, and other products. It’s a very good idea to ask everyone using your tub to take a shower beforehand; this also helps to maintain the proper alkalinity balance in the water. 

Why Does Mould Grow in Inflatable Hot Tubs? 

As comfortable as you find your cosy inflatable hot tub, it’s an even more suitable environment for many kinds of mould. The combination of humidity and warmth is just what they are looking for, especially on surfaces that aren’t exposed to sunlight. 

Mould can develop on the inner walls, jets, pump, and even the hot tub cover. When this gets out of control, the true root cause is usually a lack of proper maintenance. Knowing this is, of course, of limited use when you’re already looking at an apparently hopeless mould infestation. How, then, do you clean mould from inflatable hot tubs that have been neglected too long? 

Preparing Your Inflatable Hot Tub for Cleaning 

Removing a mould infestation from your inflatable hot tub probably isn’t the biggest project you’ll take on this week, but a little planning and preparation won’t go amiss. Before you pull on your gloves and start wielding a scrubbing brush, it is essential to prepare your inflatable hot tub properly in order to make the rest of the process that much easier.  

Here’s a step-by-step guide on what to do to prepare your hot tub for cleaning: 

Step 1: Turn Off the Power and Remove Debris 

First, ensure that the electricity supply to your hot tub is turned off; any experienced electrician will tell you that it’s better to physically plug it out rather than relying on a switch, especially when water is involved.  

Next, remove any large debris, such as leaves and twigs, from the water. A spa net makes this job a lot easier and less icky, though you can also use your hands. The purpose behind taking out any foreign objects is to prevent blockages from appearing in the drainage valve. 

Step 2: Disconnect and Clean the Filter 

Next, we’ll remove the filter casing (you’ll generally find this just before the pump) and take out the filter cartridges. You will often find mould growing on these components, even though the hot tub itself appears to be clear. 

Clean the filter housing and cartridges using a mild detergent and an old toothbrush if necessary. When all the dirt has been dislodged, simply flush it out using a garden hose. Regular cleaning can expand the life of your filters considerably If the cartridges appear worn or discoloured, though, consider replacing them. You should certainly swap them out for new ones after their lifespan, as recommended by the manufacturer, has expired; this usually means every 12 or 24 months. 

Step 3: Drain the Inflatable Hot Tub 

Now, it’s time to drain the water from your hot tub. This takes a little forethought. If you don’t have a sewage drain you can run a pipe to, you’ll generally let your hot tub drain onto the ground outside. 

In this case, it’s important to ensure that the hot tub water, as well as the chemicals it contains, won’t ruin the plants in your garden. You certainly don’t want it to spill over onto your neighbour’s property, while allowing it to seep into nearby ponds or watercourses can have some devastating environmental effects you’d probably prefer to avoid.  

Once you’ve identified a safe spot for the water to drain to, this chore is quite straightforward. Simply connect a garden hose to the hot tub’s drainage nozzle, open the valve, and direct the water away from anywhere it can cause damage. It can take quite a while for a large tub to drain fully, so take this opportunity for a tea break. 

Cleaning Mold from Your Inflatable Hot Tub 

Once your hot tub has emptied, you can finally get started on the cleaning itself. Here’s how to remove mould from an inflatable hot tub, step by step: 

Step 1: Clean the Exterior 

Begin by wiping off the outside of your hot tub’s cabinet using a soft cloth and water. Avoid using a scrubbing brush, as it can damage the material, especially wood veneer. If there are any kinds of detergents you need to avoid, this will be mentioned in the owner’s manual supplied by the manufacturer. 

Step 2: Clean the Interior 

Next, clean the inside of the hot tub (the basin or shell that holds the bulk of the water). A soft cloth and soapy water should be all you need, though some gentle work with a scouring pad used for washing dishes may be necessary. Make sure to get into all the nooks, niches, and crannies, as mould loves to hide in hard-to-reach areas. If you don’t remove as much of it as possible, it will simply bounce back and spread again the moment your back is turned. 

Step 3: Focus on Stubborn Stains and the Water Line 

After cleaning the interior, pay special attention to stains that remain even after gentle scrubbing, as well as any limescale buildup around the water line. These blemishes are often formed when minerals dissolved in the water combine with cleaning chemicals, oils, and dirt. This combination sometimes forms a hard crust that adheres tightly to the hot tub’s surface. This can be difficult to remove, but it is possible; just have some patience. 

Step 4: Choose the Right Cleaning Solution 

With most of the ordinary dirt and grime now out of the way, it’s time to pick a disinfectant – whether mild or industrial strength – to kill mould colonies and prevent them from infesting your hot tub once again. There are a number of cleaning solutions suitable for removing mould from your inflatable hot tub. Some popular options include: 

  • White Vinegar: This natural cleaning agent is highly effective at removing mould; neither the spores nor the mature fungus tolerates high levels of acidity well. It’s also safe and very easy to use: simply mix equal parts water and white vinegar in a spray bottle and apply it to the mouldy areas. Let it sit for at least an hour before wiping it off with a soft cloth.  
  • Mild Detergent: Any commonly used, mild liquid detergent, such as dish soap, can be used to clean mould from your hot tub. Mix a small amount of detergent with water and use a soft cloth to clean the affected areas.  
  • Bleach: Bleach is a powerful mould remover; you will generally dilute it to clean your hot tub. Mix one part bleach with ten parts water and dab the solution onto the mouldy areas. Let it sit for a few minutes before wiping it off with a soft cloth. You should be cautious when using bleach, though, as it can damage the material the hot tub basin is made of. Often, this shows up as discoloured patches that can’t be repaired.  
  • Commercial Cleaners: There are specially formulated commercial detergents available for cleaning mould from inflatable hot tubs. Unlike regular chlorine bleach, these chemicals are designed to be gentle on the materials hot tubs are commonly made of. While they are quite effective at removing mould, they can also be rather pricey.  

Step 5: Rinse and Dry 

After cleaning your hot tub, thoroughly rinse it with water to remove residues of whatever cleaning product you used. Skipping this step will mean introducing unwanted chemicals into the hot tub water, leading to unpredictable problems down the line.  

Once your hot tub has been rinsed out thoroughly, you’re ready to refill it with fresh water and continue using it. If you plan to store your inflatable hot tub, however, it’s essential that you allow it to air-dry completely before folding it. Any lingering moisture will provide a haven for mould to grow in, meaning that all your cleaning efforts will have been for nothing. 

Preventing Mould Growth in Your Inflatable Hot Tub 

While cleaning mould from an inflatable tub isn’t exactly backbreaking work, it’s still less effort to prevent this problem from arising in the first place. To curtail mould growth in your inflatable hot tub, you only need to do the following: 

  • Maintain Proper pH Levels: Keep the pH levels (i.e. the acidity) of your hot tub water between 7.2 and 7.6. This will put a damper on the growth of all kinds of microbes, mould and algae. 
  • Shower Before Using: Rinsing off before using your hot tub will remove dirt, body oils, and cosmetics from your skin, preventing these impurities from entering the water and contributing to mould growth.  
  • Clean and Replace Filters Regularly: Regularly clean your hot tub filters and replace them when damaged or worn out in order to maintain effective water filtration and prevent mould from gaining a foothold.  
  • Use a Hot Tub Cover: A hot tub cover will help keep debris, like wind-blown leaves, out of your hot tub. These often carry mould spores or provide food for fungus to grow. 


Mould is a fantastic way to completely ruin your inflatable hot tub’s appearance as well as the experience of those using it. While mould spores exist all around us, you don’t have to allow them to infest your hot tub. Keeping up with maintenance and cleaning should prevent any major buildups of mould from occurring. If it does become a problem, though, you can always drain the water and clean mould from an inflatable hot tub.