Alder cones of the black alder (Alnus glutinosa), have long been part of the proven and natural water care in aquaristics. Alder cones not only promote the well-being of the aquarium inhabitants, but also increase the spawning readiness of the animals, as well as their vitality.
The high content of tannins (tannins) in the alder cones significantly reduces the density of bacteria in the free aquarium water and has a slight pH lowering effect.
Of course, alder cones are also suitable as a beautiful decoration in any aquarium.
By the way - our alder cones are at least 2 cm. large and some even larger.