Clean the water tank - how, how often, with what?

Water tanks are nowadays a major topic for motorhomes and caravans. In some other areas, however, also fresh water tanks are occasionally found. The same applies to all tanks: Regular cleaning with suitable means is absolutely necessary in order to maintain a safe water quality. How, how often and in which way the tank should be cleaned, and what else is there to note, can be read here.

3-step cleaning

When cleaning tanks, you should stick to the proven 3-step principle:

  • Purification of algae and bacteria
  • disinfection
  • descaling

Purification of algae and bacteria

For the cleaning of bacteria and algae it is best to use a suitable and suitable cleaning agent. For example, in caravans, MultiMy's KeimEx has worked well for years. It has to work overnight.


When disinfecting it is essential to ensure that the disinfectant contains a strong oxidant and silver ions. They also protect the water from recontamination after the first disinfection. A combination of chlorine and silver ions is optimal in most cases.

One should pay attention to the manufacturer's information when dosing. Water containing silver ions can be drunk without hesitation, as long as the product has not been heavily overdosed. Silver ions should be added to the water even when the tank is in operation.


There are suitable decalcifying agents for decalcifying the water tank. Also, they must under no circumstances be overdosed, as otherwise they may possibly attack cables or small parts in the system. Descaler also removes bad odors from the tank.

Decalcification is important because limescale deposits can be an excellent breeding ground for bacteria. Regular descaling is therefore important.

How often clean

Basically, you should clean the tank at least twice a year, moreover, if necessary. If the tank is in continuous operation, no more frequent cleaning is required as long as enough silver ions are added to the water.

Tips & Tricks

If the tank in the camper is not used for a long time, it should be filled. Again, it is important to admit appropriate remedies against re-germination.

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