5 Low Light Floating Aquarium Plants

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As an aquarium hobbyist who has not explored the world of floating plants, you are missing out on a whole dimension for your planted aquarium.

Floating plants not only add to the beauty and charm of your fish tank but offer several other benefits. If your aquarium does not have a lid, floating plants can be a great addition to your tank.

Besides, floating plants can look great from any side you view the tank. Some floating plants have a fascinating root system that hangs down into the water, adding more definition and character to your terrarium.

Like any plant, floating aquarium plants also need light to grow and thrive. However, a few aquatic plants can thrive in minimal lighting conditions which is exactly what we’ll be discussing today.

Here are my top picks for floating plants that do not require artificial lighting:

1. Duckweed 

Duckweed is a popular choice for aquariums for its ability to reduce the toxins in the water. It feeds on nitrates and phosphate which will keep your fish and the rest of the aquatic life safe.

Duckweed is a beautiful plant with an attractive appeal and short hair-like roots. The hair-like roots can grow longer if they do not receive enough nutrients which leads to an interesting perspective.

In short, if your duckweed displays longer roots, it means that your aquarium water is clean of phosphates and nitrates.

Naturally, this also means that the plant may have difficulties finding the nutrients it needs. So, nutrient supplementation may be necessary.

Small fish like Mosquito fish, Tilapia, Grass Carp, Goldfish, Cichlids, etc., love to nibble on duckweed and can benefit from the high protein content of the plant. It is also a laxative for fish and helps clean out their intestines.

This will lead to more fish poop in the tank which will create more nitrates and phosphates which your plants will feed on.

And the cycle keeps going.

Requirements

Duckweed does not require special care and can thrive in almost any type of tank, water, and lighting situation. These plants do not require full-spectrum light or several hours of sunlight to grow. However, providing the plant with Seachem Flourish Trace Elements during the weekly water change can help duckweed thrive better. You also want to ensure that the aquarium surface is calm and tranquil, as even small currents can slow down its growth significantly.

Overall, duckweed is an undemanding plant and a safe option for aquatic hobbyists who cannot provide full-spectrum light for their tanks. It is also a low-maintenance plant, making it an excellent choice for beginners.

2. Hornwort 

Hornwort is one of the easiest tank plants to care for, with a fast growth rate. It is a hardy plant that can tolerate different conditions and is predominantly native to Canada, U.S. Virgin Islands, Alaska, North America, and Puerto Rico.

Aquarium hobbyists prefer this plant for its fluffy-looking stems and tall appearance. Hornwort absorbs its nutrients from the water, keeping the tank clean for your fish.

The plant also has allelopathic abilities, meaning it can produce chemicals to prevent the growth of other species in the aquarium. 

This is good news for aquarists dealing with algae overgrowth constantly.

Requirements

Hornworts can grow up to 120 inches in height. It might be wise to invest in a tank of at least 15 gallons to provide your hornwort with the necessary space to achieve its growth potential.

These plants enjoy a water pH of 6.0-7.5 and thrive best in temperatures of 59-86°F. Hornworts are not fussy about the lighting requirements and show healthy growth even in moderately lit tanks and low-light environments.

If you wish to see faster growth, plant your hornwort in a warmer tank instead of a brighter tank to achieve the best results. However, if you plan on growing hornwort in a warm tank, you may have to supply additional nutrients once a week to ensure healthy plant growth.

Hornwort has few demands and is one of the best plants for any aquarium. It is a hardy species that can offer a safe hiding spot for fish fry and keep the algae levels down in your tank.

Regular trimming can prevent the plant from dominating the tank and add more color, depth, and character to your aquarium.

3. Amazon Frogbit

The amazon frogbit is one of the easy-to-maintain aquarium plants with a minimal lighting requirement. The plant is native to the Central and South American regions.

It is also known as the South American sponge because of its thick and spatula-shaped leaves with spongy undersides.

The amazon frogbit is one of the popular choices among plant aquarists due to its ornamental nature and aggressive growth rate. The plant also produces pretty white-colored flowers, making them look mesmerizingly beautiful.

Requirements

The frogbit belongs to the Hydrocharitacea family and can grow up to 20 inches in height. They show fuller growth in freshwater with a pH of 6-7.5 and a temperature of 64–80° F. The best part about planting a frogbit in your aquarium is that they do well in medium-lit environments. They propagate through division and add a beautiful depth of green to your tank. 

Amazon frogbit requires moderate illumination levels. Avoid lighting sources with very high intensity, or you can burn the leaves. Keep the light duration for this species between 8 – 10 hours per day.

However, providing them with very-low lighting conditions can stop the growth and cause the plant to get sick. Besides, the plant does not do well in fast water currents due to its long and delicate roots.

For a fuller and healthy growth of the frogbit plant, supplement your tank water with a liquid fertilizer whenever necessary to provide it with the essential nutrients.

However, if you keep a lot of fish, snails, etc., fertilization is not mandatory as the plant will absorb its nutrients from the available fish waste.

4. Cabomba Caroliniana

Cabomba caroliniana is an aquatic perennial plant native to North and South America. Also known as Fanwort, it is a floating aquatic plant with short and fragile rhizomes.

It grows predominantly in streams, smaller rivers, lakes, ponds, sloughs, and ditches, and the leaves are of two types – submerged and floating. Fanwort produces small white flowers on the stalks rising from the tips of the stems.

Cabomba Aquatica can grow up to about 23 inches in length. One of the aspects of the Cabomba plant is that the leaflets look slightly oval and broad and do not overlap with each other.

Requirements

The Cambomba prefers a water temperature of 68 – 82 °F and a pH of 6.0 to 7.5. Several aquarium hobbyists vouch that the best growth was at pH 6.5. The plant shows the best growth in medium lighting. Cabomba exhibits decent coloration and vigorous growth of shoots in moderately lit tanks.

However, Cabomba cannot thrive in poorly lit environments. You may compensate for the low lighting environment by relying on CO2 injections. Fanwort requires at least 10 hours of moderate-intensity light to meet its needs.

Cabomba grows primarily in loose substrates as they do not root deeply. Although, the plant can grow in any substrate as it absorbs nutrients predominantly from the water column.

Cabomba may be the best choice for your tank if you want to create a Jungle-like aquascape. It absorbs the excess nutrients from the water and the harmful chemicals emitted from fish waste.

They can help keep your water free from nitrates, CO2, ammonia, and phosphates and counter the algae population quite effectively

Not to mention, Cabomba acts as a buffet of biofilm, providing newly hatched fry and shrimplets their first food.

5. Dwarf Water Lettuce

Dwarf water lettuce is an excellent aquatic plant choice for beginners and experienced aquarium hobbyists. It offers a great look and is easy to maintain. They also tolerate a wide range of tank conditions and environments.

Dwarf water lettuce, also known as Pistia stratiotes, is a herbaceous perennial plant. This one is native to tropical and subtropical climates and typically grows in massive lakes and near open river banks.

Water lettuce generally floats on the water’s surface, providing your aquatic life with cover from excessive heat and light.

Besides, the roots extend pretty deep into the water and fall into the water column, developing a curtain of tendrils for fish and inverts to move through.

This will help small fish and fry to use the plant as a hiding spot against predators or when stressed.

Requirements

Growing dwarf water lettuce care is moderate. While this one is a relatively small-sized species, you will still need an aquarium of at least 10 gallons for it. A small tank can create unnecessary challenges for the plant to thrive. The plant produces lengthy roots, which require a minimum of a 10-gallon tank. 

Dwarf water lettuce tolerates a generous spectrum of water conditions. These plants grow best in tropical environments. Dwarf water lettuce requires a water temperature of 72°F to 86°F and a pH of 6.0 to 7.5.

They prefer soft to medium-hard water. If you are worried about poor lighting conditions, dwarf water lettuce may be right up your alley. These plants do not need direct sunlight to stay healthy.

Dwarf water lettuce prefers slightly shady conditions and does not do well in brightly lit environments. Bright light can scorch the water lettuce leaves. An ideal light setup for this plant would be using full-spectrum T8 or T5 small-sized bulbs. 

Like any aquatic plant, dwarf water lettuce absorbs the nutrients from the environment, prevents algae from its fuel, and prevents algae accumulation.

It removes harmful toxins from plant and animal waste and keeps the water clean. It floats on the water’s surface in small florets of stocky leaves, looking like cute little lettuce or cabbage heads floating.

The Dangers of Too Much Light for Aquarium Plants

It is not uncommon for some aquarium hobbyists to see aquarium lighting as a stylish design feature. However, it is a practical necessity.

The plants and animal life in your tank need ambient and artificial light to survive and inhibit healthy growth. However, flooding your tank with excess lighting can upset the ecosystem. 

Although aquarium plants tolerate light better than the fish, shrimps, and other animal life in your tank, the real issue is the algae accumulation.

Too much light can result in algae formation, which can feed off the excess nutrients, multiply, and raise the ammonia in your tank to harmful levels.

Also, it’s worth noting that algae grow everywhere, including the plants themselves. This can prevent your plants from performing basic photosynthesis due to the algae restricting their access to sunlight which is effectively a death sentence. 

Providing adequate lighting for your aquarium plants can help the plant to grow well and benefit your fish. That’s because, although plants require different levels of lighting, they all need lighting nonetheless.

Otherwise, they won’t be able to feed properly and will die. 

Conclusion

With so many different species of floating aquatic plants, finding the one that fits your aquarium can be challenging. However, once you find the right mix of floating plants for your tank, you’ve come that much closer to creating the perfect ecosystem.

Floating plants can protect the fish in your tank from high-intensity lights during the day.

Besides, floating plants can promote aeration in a planted aquarium, regulate oxygen, and help the fish to breathe better.

Floating aquarium plants are often as helpful as filters in removing toxic fish wastes and bacteria in the aquarium.

More importantly, floating plants can help fish avoid diseases and provide a breathtaking space to hide and play.

Get some of these low-light floating plants for your tank and watch them add natural beauty and elegance to your aquarium.

avatar I’m Fabian, aquarium fish breeder and founder of this website. I’ve been keeping fish, since I was a kid. On this blog, I share a lot of information about the aquarium hobby and various fish species that I like. Please leave a comment if you have any question.

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