How to Keep 5th Wheel, Caravan & Motorhome Water Clean, Fresh & Safe

Whether you’re heading off for a weekend break or a longer tour, clean water is one of those things you only notice when it goes wrong. In an RV, your water system works hard — and if it isn’t looked after properly, it can quickly develop unpleasant tastes, smells or, worse, bacteria.

Even if you don’t drink the water from your tank, you’re still exposed to it through showers, washing up and rinsing food. For anyone with a weakened immune system, poor water hygiene can be more than just inconvenient.

Thankfully, keeping your RV water fresh and safe is mostly about routine and using the right products.

Why Cleaning Your RV Water System Matters

Running the taps and topping up with fresh water isn’t enough on its own. Over time, water tanks and pipework can develop:

• Biofilm (a slimy layer bacteria love)

• Limescale

• Sediment

• Stale water residue

That’s why your water system should be thoroughly cleaned at least twice a year, and ideally:

• Before your first trip of the season

• Every few weeks during heavy use, especially in warm weather

• After long periods of non-use

• Before winter storage

• Any time the water smells or tastes off

For UK fifth wheelers and motorhome owners alike, it’s also worth remembering that water adds weight fast. At roughly 1kg per litre, travelling with a full tank can quickly eat into your available train weight, so many owners choose to clean and refill once they’re pitched rather than carrying excess water on the road.

How to Clean an RV Water System Properly

Drain Everything Down

Start by fully draining the water tank, pipes and taps. Once empty, close the taps and — if you have access — gently clean the inside of the tank with a soft brush and mild disinfectant. Avoid harsh household cleaners, which can leave residues behind.

Rinse thoroughly before refilling.

Use a Specialist Leisure Vehicle Water Cleaner

Refill the tank with fresh water and add a dedicated motorhome sterilising product at the correct dilution.

Two of the most trusted options among UK fifth wheelers are:

• Puriclean tablets: widely recommended by motorhome manufacturers and clubs: Amazon link

• ProClean liquid: designed specifically for leisure vehicle tanks and pipework: Amazon link

Both are consistently well reviewed and commonly recommended in owner forums. Always follow the instructions and check your tank manufacturer’s guidance if unsure.

Flush the System Through

Leave the solution in the system for the recommended time, then flush all taps and pipework with clean water until there’s no taste or smell left.

Clean or Replace the Water Filter

If your system has a filter fitted, don’t skip it. A dirty filter can undo all the cleaning you’ve just done.

Popular products among UK 5th wheelers for filtering and tank filling include:

• Waterdrop inline water filters (reduces bacteria): Amazon link

• Food-grade refilling hose: Amazon link

Simple Habits That Keep Water Fresh

A few everyday habits go a long way:

• Refresh the water every few days

• Use a dedicated food-grade hose — never a scummy site hose!

• Wash hands before handling tank caps or connectors

• Don’t carry more water than you’ll realistically use while travelling

UK trucks and fifth wheel combinations can run close to their weight limits, so keeping travel water to a sensible minimum helps stay legal and stress-free.

Storing Drinking Water Separately

Some owners prefer to store drinking water outside the main tank, which can make sense if done properly.

Best practice includes:

• Use fresh water daily

• Store in food-safe containers (not reused soft drink bottles)

• Keep bottles out of direct sunlight

• Chill if possible to slow bacterial growth

We'd suggest using a filter for any water you store to reduce chemical and bacterial content prior to storage: Amazon link. For longer storage, water purification tablets ( Amazon link ) can offer extra peace of mind, but they should support — not replace — good hygiene and regular refreshing.

Clean Water, Better Touring

Keeping your fifth wheel’s water system clean doesn’t take much effort, but it makes a huge difference to comfort, confidence and health while travelling.

With regular cleaning, sensible storage and a bit of weight awareness — especially important for UK fifth wheel setups — you’ll avoid unpleasant surprises and enjoy better-tasting water wherever you park up.

Have your own water-care tips? Share them in the comments and help your fellow fifth wheelers travel smarter!