Mussels are effective purifiers of Baltic Sea water. Each small mollusc filters several liters of water per hour, and eats up substances such as nitrogen and phosphorus that would otherwise feed algae growth in the sea. Because the blue mussel in particular is so common here, it is estimated that all mussels together filter the entire volume of water in the Baltic Sea at least once a year. This compares to the inflow and outflow at Denmark, where it takes around 20 years to replace the Baltic Sea water.

And the mussels are incredibly beautiful too, just think of how an opened BLÅMUSSLA (Blue mussel) actually forms a heart!