How to Clean Your Caravan Water Tank
Keeping your caravan’s water tank clean is about protecting your health and your investment.
At Rockingham RV Centre, we’ve seen firsthand how a simple maintenance routine can prevent costly caravan repairs and keep you safely on the road.
The Importance of Regular Caravan Tank Cleaning
Even if your water looks crystal clear, bacteria and biofilm can quietly build up inside your tank, especially during Western Australia’s warmer months or when your van sits unused between trips.
A clean water system ensures:
- Safe drinking and cooking water for you and your family
- Protection against mould, algae, and harmful bacteria
- Better performance from your water pump and appliances
- No unpleasant odours throughout your caravan
- Extended lifespan of your entire water system
Also Read: How to Upgrade and Maintain a Used Caravan
How Often Should You Clean Your Water Tank?
- Every 3-6 months, if you’re travelling regularly
- Before and after long trips, particularly if you’ve filled up from unfamiliar sources
- Immediately, if you notice strange smells, cloudy water, or reduced flow
- Before storage, if your caravan will be sitting unused for extended periods
📅 Cleaning Frequency by Travel Type
| Travel Style | Recommended Cleaning |
|---|---|
| Full-time travellers | Every 2–3 months |
| Frequent weekenders | Every 3–6 months |
| Occasional trippers | Before & after every trip |
| Long-term storage | Before storing & before next use |
| WA summer travel (hot months) | Every 6–8 weeks |
| After unfamiliar water source | As soon as possible |
If you’re heading off on a long trip soon, our guide on caravan towing tips is worth a read before you hit the road.
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What You’ll Need
🧰 What You’ll Need
- ✅ Food-safe caravan tank cleaner (or household bleach)
- ✅ Clean water hose (preferably food-grade)
- ✅ Protective gloves
- ✅ Clean cloths or towels
- ✅ Bucket (optional, for mixing solutions)
- ✅ Measuring jug for accurate bleach dilution
Most of these supplies — including food-safe tank cleaner, hoses, and replacement fittings — are available through our caravan parts and accessories range.
Step-by-Step Cleaning Process
Empty the Tank Completely
Turn off your water pump and open all taps, including hot water, to drain the system thoroughly. Don’t forget to open your drain valves. You want every drop out before you start cleaning.
Add Your Cleaning Solution
🧪 Bleach Dilution Quick Reference
Based on standard household bleach (4% available chlorine) at the safe ratio of 12ml per 100L:
| Tank Size | Bleach Required |
|---|---|
| 40 litres | ~5 ml (1 tsp) |
| 80 litres | ~10 ml (2 tsp) |
| 100 litres | 12 ml |
| 150 litres | ~18 ml |
| 200 litres | 24 ml |
| 300 litres | 36 ml |
Tip: Always use plain, unscented household bleach. Avoid scented, splashless, or thickened bleach varieties — they contain additives unsafe for potable water systems.
Commercial Tank Cleaner
Follow the manufacturer’s instructions for the correct ratio. Products like Tank Clean or Camco are specifically designed for potable water systems and are available at most caravan suppliers.
DIY Bleach Solution
Mix 12ml of household bleach (4% available chlorine) per 100 litres of tank capacity. While vinegar and bicarb solutions are eco-friendly, they’re less effective at killing bacteria.
Pour your chosen solution into the tank through the fill point.
⚠️ What NOT to Use in Your Water Tank
- Scented or thickened bleach — additives are unsafe for potable water.
- Pool chlorine or industrial cleaners — far too concentrated and toxic.
- Dishwashing liquid or detergents — they foam, leave residue, and are extremely hard to flush out.
- Vinegar alone — eco-friendly but not strong enough to kill bacteria reliably.
- Boiling water — can warp or crack plastic tanks and fittings.
- More bleach than recommended — over-chlorination damages seals and plastic.
Fill and Circulate
Fill your tank with clean water, then run each tap (including the shower) until you can smell the cleaning solution coming through. This ensures your entire system gets sanitised.
💡 Pro Tip — Don’t Forget the Hot Water System: When sanitising your tank, make sure to run the hot water taps long enough to draw the cleaning solution into your hot water service too. Bacteria can build up there just as easily as in the tank itself. If your hot water unit hasn’t been flushed in over a year, drain it separately via the pressure relief valve before refilling.
Let It Work
Allow the solution to sit for 12-24 hours. This gives it time to break down biofilm and kill bacteria throughout the system. If you’re using a commercial cleaner, check the label for specific timing.
Flush Thoroughly
This is the most important step. Empty the tank completely, then refill with fresh water and run all taps again.
Repeat this process at least twice, or until there’s no trace of smell or taste from the cleaning solution.
Final Rinse and Test
Do one last fill and flush. Once you’re confident the system is clean, fill the tank with fresh water, and you’re ready to go.
Don’t Miss: Best Caravan Parks in WA — featuring potable water and dump point access.
While you’re at it, this is a great time to inspect your gas system too — check out our notes on gas modification and certification services if you’re due for a check.
Our team at Rockingham RV Centre can assess your entire water system, identify problems you might have missed, and ensure everything is working safely. Sometimes what seems like a tank issue is actually a problem with your pump, filters, or pipework — issues that often come up alongside other maintenance jobs like our lithium battery upgrades or workshop servicing.
Contact us today to help keep your caravan in pristine condition.
Recommended Reading: Tips for Inspecting a Used Caravan
Need a Hand With Your Caravan’s Water System?
Whether it’s a stubborn smell, a leaking tank, pump issues, or a full plumbing service — our certified team has you covered. We’re a Major Certified Repair Centre serving Rockingham and Perth.
📍 89 Dixon Road, Rockingham, WA
Frequently Asked Questions
Can I use household bleach to clean my caravan water tank?
Yes — plain, unscented household bleach (4% available chlorine) is safe and effective at the right ratio. Use 12ml per 100 litres of tank capacity. Avoid scented, splashless, or thickened bleaches as they contain additives unsuitable for drinking water systems.
How often should I sanitise my caravan water tank?
For most caravanners, every 3–6 months is ideal. Sanitise more frequently if you travel during WA’s hot summer months, fill from unfamiliar water sources, or notice any odd smells, tastes, or cloudy water.
Why does my caravan water smell bad?
Bad smells usually come from biofilm and bacterial growth inside the tank, hot water system, or pipes. A “rotten egg” smell can also indicate sulphur-reducing bacteria in the hot water service. A full sanitise and flush typically resolves it — if not, your water heater anode rod may need replacing.
Is it safe to drink water from my caravan tank?
Yes, provided the tank has been properly sanitised, you’re filling from a potable water source, and the system is well-maintained. Many caravanners also fit an inline water filter for added peace of mind, especially when filling at unfamiliar bores or rural taps.
Can I clean my tank with vinegar instead of bleach?
Vinegar is great for descaling and removing mineral build-up, but it doesn’t reliably kill bacteria. For full sanitisation, bleach or a commercial food-safe tank cleaner is far more effective. You can use vinegar as a follow-up rinse if you want to neutralise residual chlorine taste.
What should I do before storing my caravan long-term?
Drain the tank and entire water system completely — including the hot water service, all pipes, and the pump. Leave taps open during storage to prevent pressure build-up. Sanitise the system again before your next trip when you refill.
James Groves is a caravan industry specialist and Managing Director of Rockingham RV Centre, a trusted WA-based caravan sales and repair business with more than 20 years of industry experience. James regularly shares practical advice on caravan maintenance, towing, servicing, and touring to help Australians travel safely and confidently.
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