How to Clean the Water Tank in Your Caravan

If your caravan water has started tasting a bit off, smelling stale, or you just can’t remember the last time you cleaned the tank, this one’s for you.

Cleaning your caravan water tank might not be at the top of your to-do list (or on your to-do list at all), but it does need to be done properly and regularly. Seasoned explorers know that every extra week on the road comes down to habits like this one. 

Here’s everything you need to know, from how often to clean it through to what products to use and avoid. 

TL;DR:

• Clean your caravan water tank at least every three months
• Use food-grade sterilising products, not household bleach
• If your water smells or tastes off, a full clean and flush will usually fix it
• A water filter is a smart addition, but it doesn’t replace regular cleaning

How Often Should You Clean a Caravan Water Tank?

As a general rule, you should clean your caravan water tank every three months, or before any trip where the tank has been sitting unused for a while. We recommend adding it to your pre-trip checklist so you’ll never forget.

Water that sits still in a warm tank is the ideal environment for bacteria and algae to grow. The longer it sits, the worse it gets.

Clean your tank more frequently if:

• You’ve been filling up from unknown, untreated, or non-potable water sources
• The water has started tasting or smelling off
• You’ve had the van sitting in storage over summer
• You notice any discolouration in the water

What Do You Need For Caravan Water Tank Cleaning?

• Food-grade sterilising solution like Puriclean, Aquatabs, or Milton Sterilising Fluid (original, not scented) 
• A hose for filling and flushing
• Access to your tank inlet and outlet (check your van’s manual if you’re not sure where these are)
• Gloves (optional, but recommended)

Stocking up before your next trip? Our caravan accessories guide covers everything worth having on the road.

What to Avoid

Household bleach, dishwashing liquid, or any cleaning product not rated as food-grade or safe for potable water systems. These can leave residue that’s difficult to fully flush and may damage seals or fittings.

How to Clean Caravan Water Tanks in 8 Simple Steps

1. Empty the tank 

Drain as much water as possible through the tap or outlet valve. If your van has a drain plug, use it.

2. Mix your sterilising solution

Follow the product instructions for the correct dilution ratio. For most food-grade sterilisers, it’s roughly one litre of solution per 100 litres of tank capacity, but check the label.

3. Fill the tank with the solution

Add the sterilising solution to the tank, then fill with fresh water to dilute it correctly.

4. Let it sit

Leave the solution in the tank for at least one hour. For a tank that hasn’t been cleaned in a while or has a noticeable smell, leave it for up to four hours. 

Pro tip: Take the van for a quick 10-minute drive to slosh the solution into the top and corners of the tank.

5. Run it through the lines

Turn on the taps and run water through every outlet until you can smell the sterilising solution coming through. This cleans the pipes, not just the tank.

6. Drain completely

Drain the full tank again. If your steriliser requires it, repeat with a plain water rinse.

7. Flush with fresh water

Refill with clean water, run through all taps again, and drain. Repeat this once more to make sure there’s no residual taste or smell from the steriliser.

8. Refill for use

Once flushed, the tank is ready to refill with fresh drinking water.

What If My Tank Already Smells?

A musty or rotten egg smell usually means bacteria have had time to grow in stagnant water. The good news is that a thorough clean almost always fixes it.

For a heavily neglected tank:

• Use a stronger sterilising concentration (check product guidelines for maximum dose)
• Leave the solution in for the full four hours
• Flush at least twice with fresh water after draining
• If the smell persists after two cleans, the tank lining may need professional inspection

A persistent plastic taste in a newer van is usually just the tank off-gassing. It typically fades after a few fill and flush cycles, but if it lingers, a food-grade sterilising clean usually resolves it.

How to Keep Your Water Fresh on Long Trips

Cleaning before you leave is a good start, but keeping the water fresh while you’re on the road is the next step:

• Fill from known sources where possible and use purification tablets if you’re in a remote area or unsure of the source. Tap water from caravan parks and towns is treated, whereas creek or dam water is not.
  
• Don’t let water sit for more than a week in warm conditions without using it or refreshing the tank.
  
• Install a water filter at the tap for an extra layer of protection, especially on longer trips. It won’t replace cleaning, but it will improve taste and catch sediment.

Keep Your Van in Top Shape with Lotus Caravans

A clean water tank is just one part of the picture. Lotus Caravans are built to go further and last longer, and we want to help you get the most out of every trip. 

If you have questions about your specific Lotus Caravans van, find your nearest dealer or get in touch with our team.