Hornwort – A Complete Guide

Introducing plants into your aquarium is a great thing for so many different reasons. From oxygenating the water to providing a visual appeal to the tank, aquarium plants have so many different benefits.

Specifically, the Hornwort is a plant that is widely popular among fish tank owners. Among both beginning and experienced fish tank owners, the hornwort could be a great addition to any freshwater tank. It is perfect for beginners because it is very easy to grow and it is resistant to different water conditions.

If you are on the search for an excellent plant that accentuates your aquarium, keep reading to find the full guide on the Hornwort plant.


About the Hornwort Plant

The Hornwort plant comes from the genus Ceratophyllum. The species name is Ceratophyllum demersum. It is found free-floating all around the world. In fact, it is native to every single continent with the exception of Antarctica.

The Hornwort is now used in freshwater aquariums everywhere. It has very hardy and resilient attributes that attract fish tank owners in having it in their tank. Because of its nature in its natural environment, it can withstand a variety of tank conditions which is great for beginners.

However, in the wild, this plant can be quite problematic.

One issue with this plant when it is in the wild is that it spreads to new areas very easily making it an invasive species. This is especially a problem in places like New Zealand where it is invading the area of native plants. This disrupts hydroelectric power generation in that area which is a huge issue among the people who live there.

But, that is only in the wild. When kept in fish tanks, they are often very successful.

The Hornwort plant actually has allelopathic abilities. This means it is able to produce different chemicals that prevent the growth of other species, thus leaving more room and nutrients for itself.

Since this plant is found almost everywhere in the world, it is highly available and stocked pretty much everywhere. This also grows its popularity and explains why they are so popular among fish tank owners across the world. Another reason why they sell so fast is because of how fast they grow. They are constantly replacing themselves, so they are more readily available for people to get their hands on.

The Hornwort plant actually does not have a specific root, unlike most other plants. Instead, it uses some of their leaves to anchor themselves in the substrate. Another way they anchor themselves is by rhizoids them grow which appears to be hair-like roots.

In a natural habitat, these usually grow to around 10 feet. But, in a fish tank, they will usually stop growing when they reach the height of the tank. However, if desired, the plant can reach 10 feet is cared for properly.

The leaves stemming from this plant are usually produced in groups of around 6 to 12. The generally only fork off once or twice, and they only grow to about an inch.

In terms of color, this plant can go from bright lime green to a darker forest-like green.

This is a monoecious plant. This means that both male and female flowers are located on the same specimen which is vitally important for reproduction.

Benefits of the Hornwort Plant

Visually appealing – Many people love the hornwort for the visual appearance it gives to the tank. It is a great option if you want to spice up your tank without putting in too much work. Since it can be both floating in the water or grounded in the substrate, it is easier to create a more dynamic look in the tank which many fish tank owners love. Not to mention, the bright green color adds contrast to the tank as well.

Allelopathic abilities – Allelopathic abilities mean that the plant is able to produce different chemicals that prevent other species from growing in the tank. This clears more room in the tank and helps provide more nutrients to the plant.

Fast growth rate – There is not a specific rate of growth for this plant, but they commonly grow 5 or more inches a week. If you want the plant to grow rapidly, brighten the lighting. This ensures a larger, greener plant — but be careful about algae growth!

Good for beginners – The Hornwort plant is one of the best and most popular fish for beginners. They are hardy and resilient, so they can stand up to a variety of different water conditions. Also, they are relatively easy to maintain.

Photosynthesis – As a plant, the hornwort photosynthesizes. This means that it will oxygenate the tank and your aquatic life. Also, it provides areas for fish to hide or find shelter in to escape either each other or the light.

Great for breeding tanks – The Hornwort plant is a great plant for breeding tanks. It is a popular choice for many species of fish. This is because it provides a shelter for the eggs and baby fish. Also, it provides tiny food for the baby fish to feed off of. It is great for purifying the water with its allelopathic abilities, so the tank will be in mint condition for successful breeding.

Easy propagation – This plant is probably one of the easiest freshwater plants to propagate. All you have to do is cut or separate one of the stems that stick out from the stem, and then set it separately. Then, it will create a whole new Hornwort plant out of itself. It really is that simple.

Resilient – The Hornwort plant is very hardy and resilient in comparison to other popular freshwater plants. Not even goldfish or other plant-eating fish will kill this plant. And if the plant does get damaged, they propagate quickly with a fast growth rate.

Requirements for the Hornwort Plant

Water – The water needs to be at certain levels in order to keep your plant healthy. For temperature, it should always remain somewhere between 59 and 86 degrees Fahrenheit. The water’s pH levels should always be between 6.0 and 7.5 (preferably closer to 7.0). The water’s hardness should be between 5 and 15 dGH.

Lighting – The lighting is very important for the growth of the plant. It should remain moderate, so the lighting cycle you have set for your fish should be completely fine. Just make sure it’s not too dim and not too bright (especially because bright lights can stimulate algae growth!)

Tank – The minimum tank size for this plant is 15 gallons. However, it is preferred that you get one that is larger since these plants can possibly grow up to 10 feet if cared for properly.

Substrate – The Hornwort plant can be either free-floating or grounded in the tank — it is completely up to you. The most important thing is to make sure you correspond to your fish’s behaviors. For example, if they are bottom dwellers who like to hide in plants, it is probably best if you ground it in the substrate. In terms of substrate, fine-grained sands are what is going to best root the plant.

Filtration – Having some sort of filter in your tank is absolutely necessary if you are going to be keeping this plant. Although there are no specific requirements, it is important to keep certain nitrogen compounds like ammonia, nitrites, and nitrates very low in the tank.

Tank Mates

Compatibility is usually never an issue when blended with different types of freshwater fish. But, it is better paired with some fish over others.

Fish who are live-bearers is the best option for pairing with this plant. Examples of these fish are mollies guppies. When mating, these types of food like to use these plants as a refuge for their fry.

If you do not want the fish to eat the plant, stay away from fish like angelfish and also certain types of snails.

However, some other types of snails can be great for this plant. They can clean debris from the “root” of the plant or from anything that shed off the plant. If you do choose to have snails in the tank, be very careful. They can multiply very quickly, so you’ll need to keep that under control which can be quite difficult. If you are a beginner, we do not recommend you keep snails with this plant, as they multiply quickly and can overpopulate your tank which is not something you want.

How to Maintain the Hornwort Plant

The Hornwort plant is quite simple in terms of maintenance.

Because of its rapid growth rapid, you must be careful to not let it become too large. If it becomes too large, it will begin to dominate the tank which is not great for the water or aquatic life.

Also, if you wish to increase the speed of growth, there are multiple things you can do. First, increase the lighting. Brighter light will help to make a larger, greener plant. Second, warm up the temperature of the tank, as it will have the same effect.

However, when making any changes to the tank, make sure you are monitoring the levels and what is happening in the tank. You don’t want your aquatic life to be harmed in the process.

As far as keeping the plant healthy goes, it is important that you follow all of the requirements listed above. Make sure the water’s temperature and pH levels are at a good level. Make sure that the lighting is at a good cycle. It should be on a low to medium cycle, so it should be turned on for about 8-12 hours a day. The longer the light is turned on, the bigger it will get. This can be good, but sometimes, it will overcrowd your tank.

Meeting all of the tank requirements for this plant is going to help it thrive and grow properly. Even though they are very hardy and resilient, it still is important to maintain it properly, so it gets all of the nutrients it needs to survive.

How to Propagate the Hornwort Plant

Hornwort propagates easily and successfully in both the wild and aquarium environments. It is probably one of the easiest plants to propagate, and anyone can do it — even beginners!

The Hornwort plant propagates using vegetative fragmentation. This means one part of the plant separates itself from the rest, and then it begins to form a new plant. Vegetative fragmentation is a common propagation method for invasive plant species like the Hornwort.

The plant itself has many smaller stems coming out of the center. These stems are the pieces that will break off to form a new plant.

In the wild, this plant propagates using an additional method. In autumn, buds grow off of these smaller stems. The buds then detach themselves from the plant and sit at the bottom of the tank over winter. This forms new plants in the Spring. This process typically does not occur when the plants are in captivity.

If you want to propagate your Hornwort plant, your best bet is to cut one of the sides off and let it form a new plant.

Once you propagate this plant successfully, you are set to treat it as you would any normal Hornwort plant. With this, it is important not to let the plant get too large. Cutting the sides that get to long is important to do in your maintenance routine.

Wrapping Up

The Hornwort often makes an excellent addition to a variety of freshwater tanks. It is ideal for both beginning and experienced fish tank owners. Its hardy and resilient attributes make this perfect for compatibility as well.

It both keeps algae and other species away from the tank, and it is safe for your aquatic life. In fact, it probably even improves your fish’s quality of life overall given its allelopathic abilities.

If you are on the hunt for a perfect freshwater plant to enhance your tank, you won’t be let down by going with the Hornwort.

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