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The algae development in hydroponic system for example is a major problem for the growers. It can affect the irrigation network and equipment (filter, pump, pipes) also the plant growth. Moreover, the fungus and bacteria expand in the algae matrix.
Today, growers use this technology to control and reduce the algae development with ultrasounds.
Cause and effect of blue-green algae
How it works ?
The device emits ultrasonic waves in the water which damage the cells of the algae. Indeed, they are neutralized by resonance. Some studies mentioned a full efficiency with 42 kWz ultrasonic radiation.
In addition, this technology can remove biofilm which is very convenient in hydroponic systems where it obstructs the flow of water.
Some types of ultrasound are also effective against pathogens such as E. coli or Legionella.
Sources:
Evaluation of ultrasonic technology in removal of algae from surface waters
https://www.waterworld.com/municipal/water-utility-management/energy-management/article/16218589/ultrasound-technology-in-water-treatment-suppressing-algal-growth-and-biofilm-formation
