No back-to-school rush due to the holiday period

Myth: Water softeners lead to increased bacterial growth and a risk of Legionella

Water softeners prevent limescale build-up in your water pipes and household appliances. Limescale is an ideal breeding ground for bacteria such as Legionella. A water softener therefore actually prevents bacterial growth!

But what happens if you’re away from home for a long time? As we know, water that stands for a long time always leads to increased bacterial growth and therefore increases the risk of Legionella. Normally, water only remains stagnant for a long time if you’re away from home for a considerable period, for example whilst on holiday.

Holiday and hygiene mode

It is therefore advisable to flush out all the pipes thoroughly when you return home. This flushing also applies to most water softeners, such as the non-electric types. However, it does not apply to water softeners that beautiful water It delivers! All our models feature a so-called “Holiday Mode”, which ensures that, whilst you’re away, the resin is regularly flushed with clean water, just as if you were at home. Water consumption remains very low; just a few litres a week are sufficient. This is therefore an important feature that comes as standard with our water softeners; many competing products do not offer this feature.

Automatic flushing

And in the unlikely event that you forget to switch on the holiday mode (this isn’t possible with our Excellence range, as it happens automatically), you can carry out a forced flush as soon as you get home and also thoroughly flush out your pipework with the hottest water possible for a few minutes.

Is a disinfection module required for a water softener?

Some suppliers use a system in which the resin beads undergo additional treatment involving the production of chlorine. That sounds impressive, but it is a pointless addition because this chlorine treatment only takes place during regeneration.

This disinfection module produces chlorine through electrolysis regeneration salt during the regeneration process. The chlorine then disinfects the resin column, which is supposed to prevent bacterial growth. But this is nonsense because this chlorine treatment only takes place during regeneration. And regeneration only occurs when you use water, whereas bacterial growth can actually occur when you’re not using any water. In fact, if you’ve been away for a while, there’s a good chance that the first regeneration won’t take place until you’ve been back home for several days. You’ll then be using water that passes through a water softener which hasn’t been flushed for weeks.

So, a disinfection module sounds like a good idea, but if you think it through, a very different picture emerges. That’s why at Mooiwater we say: “prevention is better than cure”.

Premium models do, however, feature a chlorine module

That said, our Premium models do come with a chlorine module. That’s right – sometimes customers do want one after all. And at Mooiwater, the customer is always king. 

Kassa water softener

In the TV programme Kassa broadcast on 1 April 2023, several incorrect statements done. Among other things, regarding bacterial growth. The programme’s producers made it clear that they were unaware of the state of the art in the latest water softeners. The programme incorrectly claimed that a water softener would promote bacterial growth. With the latest water softeners, however, the likelihood of this happening has become very small indeed. 

Study into bacterial growth in water softeners

As the rest of the world has been using water softeners for decades (with tens of millions of installations and for much longer than in the Netherlands), extensive research was carried out at the end of the last century into bacterial growth in water softeners in those countries. The conclusions are unanimous: water softeners do not lead to exponential bacterial growth and therefore pose no threat to public health. For example, in 2000, the British researcher Simon A. Parson conducted a new study into water softeners using ion exchangers. The study can be read here: (The effect of domestic ion-exchange water softeners on the microbiological quality of drinking water – ScienceDirect).

The case study presented in Kassa There was only one household where the water was not tapped immediately after passing through the water softener. It is therefore completely impossible to determine where the bacterial growth originated. This should absolutely not be called a “study”.

In addition:
1. As all our water softeners are fitted with a hygiene mode, bacterial growth is effectively ruled out. It may be that the scientists mentioned are not fully aware of the latest technological developments in water softeners
2. Limescale build-up in all the pipes, the shower head, the taps, the coffee machine, etc., also leads to an extreme increase in surface area and a significant roughening of the surface. This is completely ignored. So when we talk about the likelihood of bacteria, such as Legionella, adhering and therefore multiplying, limescale build-up really does play a major role. However, with a water softener, limescale no longer forms anywhere and everything remains clean and smooth. We have already discussed this with Professor Van der Hoek in Delft. Despite his commitment to commission research into this and repeated requests on our part, he has, unfortunately, never responded again.
3. Every few days, the water softener is flushed with a 100% brine solution. This brine contains the maximum amount of salt that water can absorb. The Dead Sea (with an average salinity of 33%) is nothing in comparison. Not a single bacterium survives this rinse cycle.

Misconceptions about water softeners

In the same episode of Kassa, further inaccurate statements were made about water softeners. See: Kassa makes incorrect statements about water softeners

Questions about bacterial growth in water softeners

Do you have any further questions about bacterial growth and the water softener, or do you have any other queries? Please feel free to let us know. We’d be happy to help.