Whether you live off-grid, tour in a caravan or motorhome, or cruise on a narrowboat or yacht, your drinking water passes through hoses, tanks and pumps that a household on the mains never has to think about. The water you fill up with is often perfectly good, but stored water in a warm tank can quickly pick up tastes, slime and bacteria. A simple filter and good tank hygiene make a big difference.

At a glance

  • Typical issues: stale or plastic tastes, chlorine, sediment, bacteria growing in tanks and hoses
  • Biggest risk: how water is stored and handled, not usually the fill point itself
  • Typical treatment: a point-of-use drinking water filter, regular tank cleaning, and 12V UV or a gravity filter for unknown sources

Where the problems come from

  • Hoses. Garden hoses can taint water and harbour bacteria. Use a dedicated drinking-water hose, drain it after use and keep the ends capped and off the ground.
  • Storage tanks. Water sitting for days, especially in warm weather, lets bacteria and biofilm build up on tank walls and pipework.
  • Varying fill points. Campsite, marina and service-point water is normally mains water, but you cannot always be sure of the tap or what has happened to it.
  • Off-grid sources. Water from a spring, stream or rainwater tank needs the same care as any private supply.

Filter options

Inline and quick-change drinking water filters

An inline filter on the drinking water tap is the simplest upgrade for caravans, motorhomes and boats. It removes chlorine, tastes and sediment from tank water. Our QC50 (6-month cartridge, compact) and QC100 (12-month cartridge) quick-change systems fit under a sink or in a locker, and cartridges swap in seconds with no tools. The GS10EXTRA inline filter is a 12-month option for tight spaces. Browse quick-change filter systems.

Gravity filters

Gravity filters need no plumbing, pressure or power, which makes them ideal for off-grid cabins, boats and emergency supplies. Our stainless steel gravity system uses silver-impregnated ceraULTRA FTO ceramic filters designed to reduce bacteria, sediment, chlorine and fluoride; check the listing for full specifications. See gravity water filters.

12V UV disinfection

For a whole off-grid system, or a boat or motorhome that fills from varied sources, a low-voltage UV unit treats every tap. The Atlas L8 12V UV system runs from a leisure battery. As with any UV, fit a sediment filter in front of it. Browse our off-grid range.

Keeping tanks and pipework clean

  1. Start of season: drain the system, clean and sanitise the tank and pipework with a product made for drinking water tanks, then flush thoroughly.
  2. During use: turn water over regularly rather than letting it stand for weeks, and keep the tank cool where you can.
  3. Filters: change cartridges on schedule; an old cartridge can harbour bacteria rather than remove them.
  4. End of season: drain everything to prevent frost damage and stagnant water over winter.

Off-grid homes

If your off-grid property draws from a borehole, spring, stream or rainwater, treat it as a private water supply: test it, then treat it to drinking water standards. See borehole water, spring supplies, stream and river water and rainwater harvesting, and our private water supply testing guide. If you let the property, it becomes a commercial supply; see testing for holiday lets.

Related pages

Why Wrekin Water

Wrekin Water is a family run company based in Bettisfield, Shropshire, serving more than 50,000 customers over 15 years and rated Excellent on Trustpilot. Our quick-change and gravity filters are popular with caravanners, boaters and off-grid households. Ask our team which suits your setup.

Frequently asked questions

It can be, if the tank and pipework are clean and the water is turned over regularly. Water left standing in a warm tank can grow bacteria and pick up tastes, so many caravanners fit a drinking water filter and sanitise the system at the start of each season.

A quick-change inline filter on the drinking water tap suits most motorhomes and boats, removing chlorine, tastes and sediment from tank water. For water from unknown sources, add a 12V UV system or use a gravity filter.

It is better not to. Garden hoses can taint water and harbour bacteria. Use a dedicated drinking-water hose, drain it after use and keep the ends capped and off the ground.

No. Gravity filters use no power, pressure or plumbing; water simply drips through ceramic filter elements from an upper chamber to a lower one, which makes them ideal for off-grid use and emergencies.

Follow the cartridge's rated life, for example 6 months for a QC50 or 12 months for a QC100, or sooner if flow drops. An old cartridge can harbour bacteria instead of removing them.