Look
Photo: Peter Henningsen
Horn ferns are bright green and versatile aquatic plants. Young horn ferns show rosette-like, rounded, unnotched leaves. Notches form in the leaves as they age. The fern bears its name due to its resemblance to branched deer antlers.
In some breeds, the leaves remain rather rounded, others are elongated or pinnate. As a floating variant, the horn fern grows to a height of approx. 5 cm and remains rather small, curly and squat. Rooted in the ground, it grows as an elegant, slender plant up to the water’s surface. Horn ferns are sold commercially under the name «Floating Horn Fern‘ (Ceratopteris pteridoides) and ‘Horned Horn Fern‘ (Ceratopteris cornuta).
Strictly speaking, these are two different but very similar species. A third variant is «Ceratopteris thalictroides». The finely feathered species are usually offered under this name. Contradictory information can even be found in the specialist literature about the exact classification. Aquarium lovers don’t need to be bothered by this. All horn ferns are very similar in terms of keeping conditions and appearance.
distribution
Horn ferns occur in tropical regions Asia, Africa, South America and on that Australian continent before. They live «submers», i.e. under water, as well as «emers», above water, or are purely floating plants. They live rooted in the muddy shores of rivers and lakes or drift migratory on the water surface. In the aquarium or horn ferns can also ground rooting or cultivated free-floating. Horn ferns are also suitable for planting on the banks of tropical indoor ponds.
husbandry conditions
The horn fern is a grateful and uncomplicated plant. Its attractive appearance enriches aquariums and caters to many species of fish hiding places. For leopard bushfish or labyrinth fish, the floating horn fern is an ideal breeding ground. They create their foam nests between the richly branched and well-protected leaves. In good conditions it grows very quickly and occasionally needs to be thinned out. Horn ferns reproduce all by themselves by forming small adventitious plants on the leaf forks. These can be removed and further cultivated individually.