Dwarf Water Lettuce (Pistia stratiotes) is a hardy species of floating aquarium plant. This plant comes in two different sizes. The larger water lettuce is usually used in ponds and the smaller variant is usually used in aquariums and is called “Dwarf” Water Lettuce. Water Lettuce is also called water cabbage, Nile cabbage, or shellflower.
In this guide, you will learn all the information you need to care for Water Lettuce and keep them in your aquarium.
Water Lettuce was first found in the Nile near Lake Victoria in Africa. Currently, they are found in all tropical and subtropical parts of the world. They usually grow on top of ponds and slow-moving rivers. They have also been introduced into South America and now can be found in many parts of the Amazon basin.
Water lettuce is a very productive and fast-growing freshwater plant and is considered an invasive species in parts of North America. This plant can easily escape from your tank or pond and start repopulating in the waterways. So it is important to make sure you contain them in your tank.
This plant will grow extremely fast in water bodies that have high nutrient content because of fish or human activity. They are loved by many aquarists because of the beautiful and long root structure they grow in a tank environment. The fast growth rate and densely grown roots of water lettuce make them beautiful plants to remove waste from a tank.
Water lettuce can grow light green leaves that measure 2 – 15 cm long. In the aquarium, the Dwarf variety usually grows leaves that will not exceed 2 – 3 cm. They grow densely packed leaves which is why they are called water lettuce or cabbage.
The leaves have parallel venations and develop wavy margins which give them a unique look. The leaves have tiny hair-like structures on their surface which help them to trap the air and stay floated on the water.
Their roots hang submerged in the water and collect nutrition directly from the water column. This makes them a great plant for absorbing excess nutrients and heavy metals that can cause algae blooms.
Water Lettuce has a super fast growth rate. When they get enough nutritions and light they can cover the entire tank in just a few weeks. This makes them a great plant to remove fish waste fast and effectively.
They have slightly large leaves and light can not easily pass through them. This makes life a little bit hard for any submerged plants that you might have in your tank. They can easily block the light and make other aquatic plants suffer.
Because water lettuce floats on the surface of the water, it will block the oxygen exchange in your tank. So they can easily deprive a tank of oxygen and cause the carbon dioxide to rise in your tank. Fortunately, this issue is easy to fix and just one or two air bubblers add back all the oxygen your tank needs.
Water Lettuce Care
Caring for Water Lettuce in an aquarium environment is easy and simple. These plants need nutrition-rich waters and strong lighting to thrive. Your fish or shrimp will produce just enough waste for the water lettuce to flourish.
This plant still needs water to be able to fully carpet the tank’s surface. If your tank has a fast circulation or there is a lot of surface agitation. So in order to let your Water Lettuce thrive, you just need to have good light and a fish tank with still water.
Water Lettuce can grow in any tank environment as long as they meet its basic requirements. So you can grow them in a small 10-gallon aquarium or a large pond outdoors.
Water Lettuce is a floating plant, so it will grow to fill the entire surface of the water. A larger water body or tank will naturally give them more room to grow.
The volume of the water doesn’t affect the growth rate of the water lettuce. So tank size is nothing to worry about.
Water Lettuce needs a tropical environment to be able to live and grow naturally. A stable and still tank is also necessary to make them thrive. Since this plant is mainly used to remove waste from the water, you might not need to use fertilizer in your tank. More on this later in the article.
Below is the ideal range of parameters your Water Lettuce will flourish.
- Water temperature: 72° to 86° degrees Fahrenheit
- pH levels: 6.0 to 7.5
- Water hardness: 3 – 8 GH
Dwarf water lettuce does not need CO2 (carbon dioxide). Because leaves are above the water at all times this plant will get its CO2 directly from the air and there is no need to inject CO2 in the water.
Water lettuce needs strong light to grow healthy. When they are kept in a low-light environment they will slowly start to die. So it is important to have a strong light to help them Photosynthesis.
A full spectrum light is the ideal lighting system that you can get for your tank. Your water lettuce will show their appreciation by growing super fast and healthy.
Because the Water Lettuce floats on the surface of the water it will not need any substrate. The roots will float in the water and will collect the nutrients from the water column.
Water Lettuce Propagation
Water lettuce propagates by spreading small runners. The mother plant will shoot a runner out and at the end of it, new leaves and roots will start to grow. The new plant will eventually separate from the mother plant and will produce its own runners and the cycle continues.
This means you will not need to do anything special to propagate them. Just give them the right environment they need and they will reproduce rapidly.
Maintaining this plant is easy as they grow to a manageable size. When they start to outgrow our tank you can simply remove some of them from the tank. They will thrive in a wide range of water conditions so maintaining them in your tank can be a very easy task.
With the right number of fish, Water Lettuce does not need fertilization. Their hardy nature makes them able to survive with a minimum amount of fertilization in the water.
Just a few fish and a mature tank are enough for the water lettuce to flourish. When you use fertilizers they will grow faster and reproduce faster.
The good news is that this plant has large leaves so it makes it easy for you to get a few of them out of water when they overgrow in the tank. Because this water lettuce lacks a branch structure, you will not need to prune or trim them. But some of the leaves will die so you will need to remove the dead leaves by hand.
Because of their fast growth rate, that is going to be your regular maintenance routine. You will also have to remove some of the water lettuce daily so the light can reach the submerged plants.
Because of their sensitive and fragile roots, some fish might not be good tank mates for your water lettuce. At the same time, they can block light and cause your submerged plants to die. However, with regular maintenance, your other plants can live in harmony in the tank.
But probably the best tank mates for water lettuce plants are the fish and plants that prefer to live in shaded areas.
Here are our top tank mates for Water Lettuces:
- Other live plants
- Betta Fish
- Platy Fish
- Guppy Fish
- Red Cherry Shrimp
- Blue Dream Shrimp
- Ghost Shrimp
- Amano Shrimp
- Bamboo Shrimp
- Ramshorn Snails
- Bladder Snail
- Cory Catfish
Is Water Lettuce Suitable for your Aquarium?
Water Lettuce is a great plant for removing waste and heavy metals from the tank. Unlike most aquarium plants, they will directly clean the water by absorbing the nutrients diluted in the water. This will keep the water clean and healthy for the fish or other inhabitants that you might have in your tank.
This plant needs a still surface of the water to be able to thrive, so if you have a tank that has a slow current, this plant can be a great choice.
Because they block the light, they will also help your tank to stay algae-free. But at the same time, they will also block the light to other plants so if you have sensitive plants that need strong lighting adding water lettuce to your tank might not be so wise.
Water Lettuce is a super easy to grow and maintain aquarium plants that anyone owns. Even new aquarium owners with minimum experience with aquatic plants can safely keep this plant in their tanks. By now this guide has fully prepared you to care after your water lettuce without facing any issues.
If you have any more questions, let us know by email or on social media and we’re more than happy to help!