Najas marina

Najas marina has the widest distribution of any Najas species, found on every continent except Antarctica in fresh, brackish, and occasionally marine-influenced water. Its leaves are broader and more distinctly toothed than other Najas species, bearing visible spines along their margins and on the stem, giving the plant a somewhat rough but characterful texture. It is notably tolerant of hard, alkaline, and brackish water conditions, making it an invaluable oxygenating plant for African cichlid tanks, brackish setups, and hard-tap-water community tanks where softer aquatic plants struggle. It grows freely without CO2 or special fertilisation and provides excellent cover and spawning habitat.

Light: Low to medium (15–50 PAR); adaptable to a wide range of lighting conditions. CO2: Not required; grows well across a broad range of dissolved CO2 levels. Fertilisation: Minimal — water column feeder; occasional all-in-one liquid fertiliser every 2 weeks. Placement: Midground to background; effective as floating cover or loosely anchored bunches. Propagation: Stem fragments take easily; scatter cuttings freely — plant establishes without assistance.