Najas marina

Species description

Care, breeding and tankmates

Plant profile

Placement

Midground

Can be planted in the background or left to float. Its stiff, toothed leaves provide a unique structural element in the tank.

Botanical form

Stem

Distinctive for its stiff, brittle stems and leaves that have prominent, almost spiny teeth along the margins. The plant has a robust, prickly appearance.

Growth

Fast

Moderately fast to fast, depending on lighting and nutrient availability. It can quickly form dense stands.

Substrate

None

Column fertilization

Recommended

Absorbs most of its required nutrients directly from the water column. Regular dosing of a complete fertilizer supports its rigid growth.

Root fertilization

None

Can develop roots to anchor itself in the substrate, but does not strictly rely on them for feeding.

Trimming

Regular

Trimming is best done by snapping the brittle stems. Care should be taken as the stiff 'spines' can sometimes be slightly sharp to the touch.

Propagation

Cuttings

Propagates easily by stem cuttings or natural fragmentation. The rigid fragments sink or float and quickly resume growth.

Sensitivity

Moderate

Dislikes very soft water; it thrives in harder, alkaline conditions. Like other Najas, avoid glutaraldehyde-based products.

Layout role

Midground, Background

Provides a highly unusual, almost prehistoric texture to the aquascape due to its toothed leaves. Excellent for specialized biotopes or as a breeding refuge.