Blyxa japonica – jermack

Origin: subtropic and tropical regions of East and South-East Asia
Usage: Midground, Foreground, Nano Tanks
CO2: High
Light: Medium – High
Care: Medium
Growth Form: Stem/Rosette
Growth Rate: Medium
Height: 4 – 8”
Width: 3 – 5”
Temp: 61 – 89F

Blyxa japonica, native to subtropical and tropical regions of East and Southeast Asia, thrives in the nutrient-rich soil of shallow ponds, swamps, rice paddies, and slow-flowing rivers. This plant has become a favorite in the aquarium hobby for its attractive, bushy, grasslike appearance.

Cultivating Blyxa japonica is straightforward with a few basic requirements: bright light (0.5-1 watt per liter or more), CO2 supplementation, and a nutrient-rich substrate. Under optimal conditions, this plant exhibits stunning golden and reddish hues with a compact growth habit. In less ideal lighting, it grows taller and greener, with a more elongated form. Blyxa japonica develops an extensive root system and thrives in substrates enriched with nutrients or bottom fertilizers. High phosphate levels (1-2 mg/l) encourage the growth of long stems with delicate white flowers.

Unlike many grasslike aquarium plants, Blyxa japonica does not produce long runners. Instead, it grows lateral shoots from the base, which can be easily trimmed and replanted. While anchoring can be challenging due to its buoyant nature, once established, it forms a dense root system quickly. Popularized by Takashi Amano’s Nature Aquarium layouts, Blyxa japonica provides a striking contrast to small-leaved foreground plants and adds a lush, green-golden texture to the middleground of any aquarium setup.