Hornwort (Ceratophyllum platyacanthum)
Care, watering, light and tips for Hornwort on Floravia.
Quick facts
- Family: Ceratophyllaceae
- Difficulty: Easy to care for
- Watering: every 7 days
- Light: Partial shade
- Temperature: 10–30 °C
About Hornwort
Ceratophyllum platyacanthum, known as Broad-spined Hornwort, is a free-floating, rootless aquatic plant that thrives submerged in the water column. Its stems branch profusely, adorned with finely divided, rigid, bright green leaves, giving it a dense, feathery appearance. It is ideal for cold or temperate water aquariums, ponds, and provides excellent shelter for fry and small invertebrates.
Native range
Europe, Asia, and North America
Care tips
It requires moderate to high lighting for optimal growth, although it tolerates lower light conditions. It does not need substrate, as it absorbs nutrients directly from the water; nutrient-rich water is beneficial. Maintain water temperature between 15-28°C and avoid sudden changes in water parameters, as it is sensitive to fluctuations. A common mistake is attempting to plant it in the substrate, which can cause the base of the stems to rot.
How to save a dying Hornwort
- Warning signs
- Discolored stems (brown/black), leaf disintegration, excessive buoyancy or unusual sinking.
- First aid
- Remove dead parts. If water is cloudy, do a partial water change. Ensure enough light and stable CO2.
- What kills it
- Abrupt water parameter changes (temp, pH), lack of light, or excess nutrients causing algae.
- Can it be saved?
- Yes, if healthy green stems remain. Improve water conditions and lighting. It's resilient.