Water Hyacinth

Water hyacinth is a large surface plant whose rounded leaves rise on swollen, buoyant stalks. Its hanging roots and above-water flower spikes need considerably more space than small aquarium floaters. It is best considered for a large open aquarium, a suitable outdoor container or a warm-season pond, rather than a shaded tank with little clearance above the water.

Provide strong light, warm water and a sufficient macro- and micronutrient supply. Keep water at 25 to 30 °C and pH 5 to 8. Pale leaves and slow growth can indicate inadequate nutrition or cold conditions. Aquarium cultivation is rated difficult; rapid growth outdoors in favourable conditions does not make it almost impossible to kill indoors. Its exposed leaves obtain carbon from the air, so injected aquarium CO₂ is not needed for this surface-growing use.

Established rosettes produce daughters on runners. Separate those plants to propagate, or remove them to control coverage. Thin the surface patch before it crowds neighbouring rosettes or shades the plants beneath. Keep the long roots clear of equipment intakes. This species can become invasive outside its native range: retain it in a contained system and do not release plants or discarded growth into natural waterways.