A planted aquarium is always a spectacular sight, but floating plants turn your tank from a nice aquascape to an environment that mimics what your fish would experience in their natural habitat.
Floating plants look like a real novelty, and you may wonder how to care for them or how to ensure they survive when they are not rooted in a substrate. However, many of these plants are, actually, really easy to look after. Read on for some of the best and most popular, how to look after them, and what kind of tank they suit best.
Why Keep Floating Plants In Your Aquarium?
Before choosing, why might you want to keep floating plants in your tank? Answering this question can help you decide the best species, plus work out how they go with your wider tank environment.
Floating plants are very useful for providing shade, which is one of the requirements of a large number of fish, especially those that come from shaded rainforest habitats. In addition, many floating plants come from South America, which means they are suitable for these rainforest species that prefer shade. As a result, they can keep your fish protected from bright light.
Floating plants are also great for fish that like to hang out near the surface of the water, like Betta Fish and Gouramis. These species come from rice paddies in the wild and are used to there being lots of lush vegetation near the surface of the water. As a result, including some floating plants can help you recreate the sort of hiding spaces that encourage these fish to feel at home, even leading to them creating bubble nests. As a result, floating plants can be a very useful tool if you wish to breed certain species of fish.
Many floating plants have been used to remove nitrates from industrial sewage and wastewater. Thus, they are perfect for easily creating cleaner conditions within your tank.
When might you want to avoid floating plants? Floating plants can become a problem with fish like Goldfish that like to eat plants. It can become a waste of money quite quickly if your fish just keep eating the plants you add. In addition, if they don’t get eaten entirely, some species of plants like duckweed grow very fast and when eaten by goldfish can grow back very vigorously, clogging your tank.
How To Choose Floating Aquatic Plants
Now you understand some of the purposes of floating plants, you may have a clearer idea of which you want to choose.
In general, choosing plants from a roughly similar habitat to our fish can help them thrive, such as pairing Amazonian plants like Brazilian Pennywort and Amazon Frogbit with shade-loving Amazonian Tetras.
Otherwise, think about what kind of look you are going for. For a sophisticated aquascape, mosquito fern and water wisteria have unusual shapes and geometric leaves that can add eye-catching detail.
Are you a beginner, or do you have kids? Both Brazilian Pennywort and Amazon Frogbit are really easy to take care of and almost impossible to kill.
Furthermore, what kind of habit do you want your plants to grow in? Some plants on this list are strictly floating. Others, like water wisteria, can be planted as well. Combined with whether they flower and how easily, there are a multitude of appearances to choose from.
1. Amazon Frogbit
Amazon Frogbit is a small, round-leaved floating aquatic plant that is often mistaken for the invasive water hyacinth.
- Appearance: Amazon Frogbit has small, bright green, round leaves that float on top of the surface of the water in your tank. It is very fast growing and it can reproduce both via the pollination of its flowers, as well as asexually, from bits of the plant that break off. As a result of this habit, it takes some work to keep under control. Additionally, if you keep fish like goldfish that nibble at plants, you may find this plant reproduces prolifically as the fish feeding on it stimulate its natural growth and reproduction.
- Origins: Like its name suggests, this plant comes from the Amazon Rainforest. Here, it floats on top of the surface of water, providing shady cover.
- Suitability: Amazon Frogbit doesn’t enjoy bright light that much. In fact, light that is too bright, such as incandescent or LED bulbs, can make its leaves discolored. Therefore it’s best to keep it in a shaded tank, which makes it perfect for species like the neon or cardinal tetra that come from shaded rainforest habitats and also don’t like bright light.
Author’s Note: This plant can even work as an indicator of the nitrogen levels in your tank and its roots grow longer the more nitrates there are.
- Temperature: 65 – 80 F/18 – 27 C
- pH: 6.0-7.5
2. Brazilian Pennywort
Brazilian Pennywort has small round leaves just like Amazon Frogbit, with an additional creping habit that makes it extremely popular.
- Appearance: As stated, this plant has attractive round leaves and long stems that can grow relatively broadly, up to over 20 cm. It mostly is known as a mat-forming plant, floating on the surface of the water, but this trialing habit shouldn’t be overlooked and it is often sold in pots. In fact, you can grow it in a combination of both aspects.
- Origins: Like its name suggests, this plant comes from Brazil, and the rivers and tributaries in the Amazon rainforest. This makes it a perfect plant for a tank with shade-loving Amazonian fish such as many species of tetras.
- Suitability: This is a timeless favorite plant for both beginners and intermediate aquarists alike. Due to its creeping habit, it can be a good choice for semi-aquatic habitats such as if you want to keep turtles or African dwarf frogs along with your fish in a terrarium that has both submerged and above-ground elements.
- Temperature: 70 – 82 F/21 – 28 C
- pH: 6.0 – 8.0
3. Water Primrose
There are many plants named water primrose but the one we are looking at here is floating water primrose or Ludwigia Repens. In fact, the family has over 200 plants in it!
Not all of them are floating so be careful which one you get hold of. The water primrose in your local aquatics store may be the floating or planted variety, so it’s best to double-check.
- Appearance: This plant has attractive red foliage that fades to green the higher up the stem it is. It can, in fact, live above the water in its planted varieties.
- Origins: This plant comes from South America, but it can be grown in tanks with plants from a variety of places around the world due to how hardy it is.
- Suitability: This is one of the plants that has the biggest payoff for beginners because it looks so striking but is so easy to take care of. It honestly works really well in any tank as an underrated option, a key reason why it makes this list.
- Temperature: 68 – 78 F/ 20 – 26 C
- pH: 5.5 – 7.5
4. Water Wisteria
Hygrophila or water wisteria isn’t related to the purple wisteria that is popular in many gardens. Instead, it is a floating plant that can also be grown in a soil substrate. Like water sprite, which shares the same combination of either floating or upright habits, it has branching, pointed leaves, yet those of water wisteria are somewhat finer.
- Appearance: Water wisteria is a striking bottle green color and adds a vibrant appearance to your tank. Its long fronds provide the perfect place for many fish species to lay their eggs, as well as providing shelter for shy fish or fish that like to build nests such as betta fish. Water Wisteria adds loads of interest to your tank due to the way it changes the shape of its leaves in response to environmental stimuli. This isn’t fully studied yet but depending on your light levels, tank position, and other factors, you may see rounded simple leaves or multi-branched leaves. This gives your tank the look of having a huge variety of plants.
- Origins: This plant originally comes from areas of Asia such as India and Bangladesh where it grows in rivers and streams.
- Suitability: Water wisteria is really easy to cultivate. Therefore it is perfect to combine with Rasboras and other fish from these areas although it can go well with many kinds of fish so long as they like the shelter. Water wisteria likes bright light and grows well when it gets plenty of this. Brown or yellow leaves are a sign your plants are not getting enough light or nutrients.
- Temperature: 72 – 84 F/24 – 29 C
- pH: 6.5 – 7.5
5. Mosquito Fern
Mosquito fern is a very distinctive plant that can grow rapidly and easily cover the surface of your aquarium. However, once you know more about its natural habitat, it’s possible to keep it in balance with your fish and other plants, making an unusually shaped addition to your aquarium.
- Appearance: Mosquito fern looks very different from other ferns. With sharp edges and geometric leaves, it quickly covers available water surfaces with whorls of green and red, making it a really special addition.
- Origins: Mosquito fern is in the genus Azolla and various species originated in Southeast Asia where they have been used as a natural fertilizer for rice paddies for over 100 years. These plants would grow quickly and reduce the growth of weeds before dying off and leaving nutrients in the paddy that would help the rice grow.
- Suitability: This plant is suitable for beginners but bear in mind you may need to manage it a bit due to its prolific growth habit. In addition, the fact it introduces nitrogen to the water when dying means that it can encourage the growth of algae, so it can be wise to invest in some algae-eating fish if you keep this plant in your tank.
Author’s Note: This plant is relatively heat sensitive so if you are worried about it growing too intensively, just ensure your room with the aquarium is on the cooler side.
- Temperature: 68 – 78 F/20 – 26 C
- pH: 5.5 – 7.5
6. Dwarf Water Lettuce
Dwarf water lettuce, or Pistea Stratioides, is an attractive floating plant that forms rather dense and heavy rosettes. As a result, it can be a bit too much for a small tank, but it is very useful for a larger tank or as additional decoration for the surface of the water. Just don’t add too much.
- Appearance: Dwarf water lettuce has round leaves with shallow folds that make them look slightly scalloped. It has long trailing routes that can be over four times the height of the plant and have a green tinge to them.
- Origins: This plant is thought to have originated on the river Nile although it is now an invasive species across the tropics.
- Suitability: This is a really useful plant for beginners as it can help prevent algal blooms. It reproduces both via flowers and pollen but also by sending out runners on which a second, smaller rosette forms. Water lettuce can help keep your tank in shape due to its medicinal properties and suitability for phytoremediation – the use of plants to clean up pollutants.
- Temperature: 72 – 86 F / 22 – 28 F
- pH: 6.5 – 7.5
7. Water Sprite
Water sprite is a great plant from preventing algae blooms that has the added benefit of being able to grow both in a substrate and as a floating plant.
If you grow it as a floating plant it has a spreading habit whereas when planted in a substrate it has an upright growth with spiky leaves that spread outwards from a dark greenish-red stem.
- Appearance: With slender, forked green leaves, it is an attractive plant that has an upright growing habit but can also be floated on the surface of the water.
- Origins: Did you know water sprite is actually a kind of fern? This plant is found all over the world although there is not much information on its source of origin. Either way, it is prolific and very successful wherever it establishes.
- Suitability: As mentioned above this is a strong and fast-growing plant. It’s generally suitable for all kinds of tanks and fish and is easy to care for. However, it can absorb nutrients from the rest of the tank, so trim it occasionally to keep it in check.
- Temperature: 72 – 82 F / 22 – 28 F
- pH: 6.0 – 8.0
Preventing Disease In Floating Aquatic Plants
All the plants on this list are relatively hardy, but to prevent disease you can keep an eye out for the following signs:
- Brown or yellow leaves, which can indicate your plants aren’t getting enough light or nutrients
- Paler leaves can indicate plants have been exposed to too much light and therefore have been burnt
- Black or rotting-looking roots
- Ragged leaves or black or ragged edges to leaves. Alternatively, this can be a sign fish have been nibbling the leaves of your plants.
Floating plants are a beautiful and easy solution for small aquariums, as well as adding character to your tank.
This roundup of 7 of the most popular species brings you the best options for beginners, as well as plants that are easy to find in general. Overall, if you want to keep a beautifully green tank with plant cover over the surface of the water, you can’t go wrong with any of these – and the added benefit is they are great at telling you if the rest of your tank is healthy too.
Author’s Note: The best fish for a tank with floating plants include Tetras and Plecos but also Betta Fish and Gouramis. Mollies, Guppies, and other livebearers also enjoy them.