More and more we come across warning signs at the water’s edge: ‘Blue-green algae: No swimming!’ This is a problem in the summer at many natural pools, such as ponds, lakes and streams. If the water contains sufficient nutrients (phosphorus) and the temperature goes up, the algae can grow explosively and present a danger.

Currently blue-green algae are sometimes tackled, but often the approach taken is to wait until they disappear on their own as the temperature drops. One way of actively tackling the problem is to add peroxide to the water. This kills the algae, but it also inadvertently kills other organisms. What’s more, the cause of the algal bloom does not disappear. The best remedy to the blue-green algae problem is to remove their nutrient source: phosphorus.

‘Zwemlust Nieuwersluis – the most attractive natural bathing pool in the Netherlands’ is also regularly disturbed by blue-green algae. On the advice of Waternet, Zwemlust decided to start removing the phosphorus using ferrous sand, which is generated in drinking water production processes. The ferrous sand binds to the phosphorus in a kind of filter, so that it is no longer available to the algae.

The result: fresh and healthy bathing water! AquaMinerals wishes everyone in Nieuwersluis and surroundings lots of bathing fun.