Water Hyacinth (Eichhornia crassipes)

Eichhornia crassipes, the Water Hyacinth, is one of the world's fastest-growing aquatic plants, producing inflated, glossy petioles, rounded waxy leaves, and beautiful spikes of lavender-purple flowers. Its dense, feathery root system is extraordinarily effective at absorbing excess nitrates and phosphates, making it a powerful natural filtration aid in large aquariums, ponds, and paludariums. Note: invasive outside its native range — never release into open water.

Requires high light (natural sunlight or very bright aquarium lighting) to thrive. Provide open surface water for free floating; does not root into substrate. Feed with a dilute liquid fertiliser every 2 weeks in aquariums. Temperature 18–35°C; sensitive to frost. Remove excess growth regularly to prevent light blockage below. Legal to sell in Belgium; illegal to release into the wild. Excellent paired with koi ponds where grazing reduces its spread.