How to Care for Hornwort in Aquariums and Ponds
Hornwort is a popular aquatic plant for both fish tanks and outdoor ponds because of its fluffy-looking stems, extremely fast growth, and ability to consume excess nutrients from the water. Learn more about hornwort care and whether it’s right for you.
What is Hornwort?
Ceratophyllum demersum is known by many common names, such as rigid hornwort, hornwart (a frequent misspelling), and coontail. In the wild, it can grow to a height of approximately 3 feet and can reach the top of any aquarium or pond. Hornwort can normally be found floating in water. However, when it is planted in substrate, it appears like an underwater bush with many long branches and side stems. The bright green leaves look similar to pine needles. They are rigid and thin, with stiff edges. Much like water sprite and java moss, hornwort has dense foliage that provides excellent protection for baby fish and shrimp.
Where is hornwort found? Hornwort can survive in a diverse variety of climates and is found on every continent except for Antarctica. It prefers to grow in bodies of still or slow-moving fresh water with lots of organic nutrients in it.
Can hornwort clean water. Hornwort is a fast-growing plant that uses waste compounds (e.g. ammonia, nitrogen, and phosphates) to grow new leaves. Hornwort can easily grow to 1-4 inches (3-10cm), if there is enough light and nutrients.
Do snails eat hornwort? Aquarium snails are detritivores and do not eat healthy plants but rather dying leaves and other organic debris. You will most likely see a pest snail eating the leaves of a plant.
Does hornwort harm goldfish? Hornwort is not eaten by most plant-eating species (like turtles, koi, African Cichlids and goldfish). One reason could be its slightly serrated leaves, hard texture, and taste, which can make it unpalatable as food.
Hornwort leaves are not completely smooth but have small bumps that give it a slightly spiky texture.
How to Care For Hornwort
This aquatic plant can live in a huge temperature range from around 50-85degF (10-30degF), so you can put it in tropical aquariums, cold water tanks with no heater, and outdoor ponds (where they can often survive the winter season depending on your climate). Hornwort thrives best when it is a floating plant. It has more light and carbon dioxide from air. While some people prefer to plant it in the substrate, others attach it to hardscape. But because it doesn’t grow proper roots, the attached ends tend to rot away. If your hornwort starts to grow out of control, make sure you trim it back so it doesn’t block the sunlight or limit gas exchange at surface.
Hornwort prefers gentle flow so ensure that the needles are not accidentally sucked up by the filter intake. It can grow under low to high light and does not require carbon dioxide (CO2) injection. Because it grows so quickly, it’s best to use it as a background plant in larger tanks (unless you have the time to constantly trim it). Due to its rapid growth, it can quickly deplete your aquarium of nutrients. You may have to add Easy Green liquid fertilizer regularly to ensure that all plants are getting enough.
Why are my hornwort leaves falling off? Hornwort can shed its needles when there is a significant change in the water parameters, lack of light, and/or if it has been exposed to chemicals such as liquid carbon or strong currents. The most common occurrence is when you first add it to your tank and the plant is not used to your water conditions. You don’t have to throw the whole plant away. Wait for it time to recover, and it will soon start growing new shoots. Also, make sure to gravel vacuum the fallen leaves to prevent excess nutrients from building up in the aquarium.
Hornwort is easily propagated by trimming off a section and floating it in a new fish tank.
How to Propagate Hornwort
In the wild, hornwort can form little buds that drop to the ground during the cold season and sprout when the weather warms out. At home, the most common method of propagation is to cut off a side shoot or trim off the top of a tall stem. A single hornwort segment will soon become a new plant, if it is allowed to float on the water surface or planted in the ground. In fact, one of the easiest ways to get hornwort is to ask around and see if any local hobbyists have some extra trimmings to give away, which they are usually more than happy to share. We do not sell Hornwort, as it isn’t able to survive shipping. However, we have many of our favourite beginner plants available for you to view.