Most hose filtration protects equipment. Filling the fresh water tank of a caravan, motorhome or boat is different, because the household will drink what passed through it, and that raises the standard for the hose, the filter and the routine in ways a garden application never does.
The hose matters as much as the filter
Use a hose designated for drinking water rather than a garden hose. Garden hose materials impart taste, are not made for potable service, and can support growth inside a coil left in the sun. A dedicated white or blue potable hose, stored coiled in a bag rather than lying in a locker, is the single biggest improvement most people can make to the taste of their tank water, and it costs less than the filter that is usually blamed for the problem.
What the filter can realistically do
An inline cartridge at hose flow gives very little contact time, so it is a sediment filter first and a taste filter second. It will catch grit, rust flakes and pipe debris from a campsite standpipe, which is genuinely worth doing before it reaches a tank that is hard to clean. It will reduce some chlorine. It will not make unsafe water safe, will not remove bacteria, and is not certified as a drinking water treatment device, so the source still has to be a supply you would drink from.
The routine that keeps tank water pleasant
Fill from a supply you trust rather than from any tap available. Run the standpipe for a few seconds before connecting, to clear whatever is standing in it. Keep the hose ends capped or joined together in storage so the inside stays clean. Drain the filter after use rather than leaving it full and warm, since a wet cartridge in a locker is a growth environment. And sanitize the tank periodically per the manufacturer's method, which matters more than any filter.
Winter, and replacement
Water left in a filter will freeze and split the body, so drain it before storage and keep it somewhere dry. Most of these units are sealed and replaced whole rather than recartridged, so note when it went into service and replace on the manufacturer's stated volume or duration rather than waiting for a symptom. The EPA notes community water systems publish annual reports, which is worth reading for a site you use regularly. Our inline filter guide compares potable rated units with garden versions.
Questions people ask about inline hose water filter
Can I use a garden hose to fill a fresh water tank?
Better not to. Garden hose materials impart taste, are not made for potable service and can support growth inside the coil.
Does an inline filter make campsite water safe?
No. It is not certified as a drinking water treatment device and does nothing about bacteria. The source still has to be a supply you would drink.
Should I drain the filter after use?
Yes. A wet cartridge left warm in a locker is a growth environment, and water left in it will freeze and split the body in winter.
Can the cartridge be replaced?
Most inline hose filters are sealed units replaced whole, so note the service date and replace on the stated volume or duration.