Rotala rotundifolia is a popular aquatic plant among aquarists. It is a fast-growing stem plant that can add a vibrant green and reddish hue to your aquarium. Rotala rotundifolia is native to Southeast Asia and is found in various habitats such as marshes, swamps, and slow-moving streams.

As an aquatic plant, Rotala rotundifolia can thrive in a variety of water conditions. However, it requires bright lighting and CO2 supplementation to grow and propagate successfully. The plant is easy to care for and can be grown without CO2 after a period of adjustment. Rotala rotundifolia is a great plant for beginners and experienced aquarists alike, as it is hardy and easy to propagate.

Overall, Rotala rotundifolia is a beautiful and versatile aquatic plant that can add color and texture to any aquarium. With proper care and maintenance, it can thrive in a variety of water conditions and provide a stunning visual display.

Taxonomy and Classification

Rotala rotundifolia is a plant species belonging to the family Lythraceae. It was first described in 1820 by Buchanan-Hamilton ex Roxburgh and was later classified by Koehne in 1880. The plant's scientific name is derived from its round-shaped leaves and the genus Rotala, which is derived from the Latin word "rota" meaning wheel, referring to the whorled arrangement of the leaves.

The species is also known by several other common names, including dwarf rotala, roundleaf toothcup, and ammannia rotundifolia. The plant is often confused with Rotala indica, another species of the same genus, but they can be distinguished by the shape of their leaves and the arrangement of their flowers.

Rotala rotundifolia is a tropical to sub-tropical perennial plant that can grow as an obligate aquatic or as a semi-aquatic. The plant has considerable phenotypic plasticity, which means that its appearance can vary depending on its environment. The submersed aquatic leaves are thin, lanceolate, and up to 2 cm long, while the emersed leaves are broader and more oval-shaped.

The species has been introduced to the United States and is considered a common weed in rice paddies and wet places in India, China, Taiwan, Thailand, Laos, and Vietnam. Its taxonomic classification is as follows:

KingdomPlantaeCladeTracheophytesCladeAngiospermsCladeEudicotsCladeRosidsOrderMyrtalesFamilyLythraceaeGenusRotalaSpeciesRotala rotundifolia

In summary, Rotala rotundifolia is a plant species belonging to the family Lythraceae, with considerable phenotypic plasticity and several common names. Its taxonomic classification places it in the order Myrtales, family Lythraceae, and genus Rotala.

Morphology and Growth Habits

Rotala rotundifolia is a versatile aquatic plant that can grow in both submerged and emergent forms. Its leaves are thin, lanceolate, and up to 2 cm long. The plant can grow as an obligate aquatic, with one growth form, or as a semi-aquatic with a very different growth form (heterophyllous) [1].

Leaf Structure

The submersed aquatic leaves of Rotala rotundifolia are thin and lanceolate, while the emergent leaves are broader and have a more elliptical shape. The leaves are arranged in whorls around the stem, with each whorl containing 4-6 leaves. The leaves are a bright green color and are smooth to the touch.

Stem Characteristics

The stem of Rotala rotundifolia is thin and flexible, allowing it to sway gently in the water. The stem can grow up to 80 cm in height and is usually unbranched. The plant's roots are thin and hair-like, allowing them to absorb nutrients from the water column. Rotala rotundifolia can grow in a variety of sediment types, including gravel, sand, and silt [2].

In summary, Rotala rotundifolia is a versatile aquatic plant that can grow in both submerged and emergent forms. Its leaves are thin, lanceolate, and up to 2 cm long. The stem is thin and flexible, allowing it to sway gently in the water. The plant's roots are thin and hair-like, allowing them to absorb nutrients from the water column.

[1] https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=2611

[2] https://www.nature.com/articles/s41598-019-51508-y

Habitat and Distribution

Rotala rotundifolia is a fast-growing aquatic plant that is native to Southeast Asia. It is commonly found in wet places and rice paddies in India, China, Taiwan, Thailand, Laos, Vietnam, and other parts of Indo-China.

The plant is a perennial and can grow as an obligate aquatic or as a semi-aquatic with a very different growth form. The submersed aquatic leaves are thin, lanceolate, and up to 2 cm long. The emersed form has rounded leaves, while submerged leaves are narrow and lanceolate. The form and color may vary with light and environmental conditions.

In the aquarium hobby, Rotala rotundifolia is a popular plant due to its ease of care, fast growth rate, and attractive appearance. It is often used as a background or midground plant in aquascapes. The plant's natural habitat is in shallow, slow-moving water with a neutral to slightly acidic pH and moderate to high lighting.

In terms of distribution, Rotala rotundifolia is now found in various parts of the world due to its introduction as an aquarium plant. It is considered an invasive species in some areas, including parts of the United States. Therefore, it is important to be mindful of proper disposal of aquarium plants to prevent the spread of non-native species.

Cultivation and Care

Rotala rotundifolia is a popular aquarium plant that is relatively easy to grow and care for. In this section, I will discuss the lighting requirements, water conditions, fertilization, and CO2 levels that are necessary for the successful cultivation of Rotala rotundifolia.

Lighting Requirements

Rotala rotundifolia requires moderate to high lighting conditions to thrive. A minimum of 2 watts per gallon of full-spectrum lighting is recommended. It is important to note that the lighting requirements of Rotala rotundifolia may vary depending on the specific species and the tank's depth. It is always a good idea to research the specific lighting requirements of the species you are growing.

Water Conditions

Rotala rotundifolia prefers soft to moderately hard water, with a pH range of 6.0 to 7.5. It is important to maintain stable water parameters to prevent stress on the plant. High levels of nitrates and phosphates can also encourage the growth of algae, which can compete with Rotala rotundifolia for nutrients.

Fertilization and CO2

Rotala rotundifolia requires regular fertilization to maintain healthy growth. A complete liquid fertilizer that contains all essential nutrients is recommended. It is also important to maintain adequate levels of CO2 in the aquarium. CO2 injection systems can be used to supplement the levels of CO2 in the water. However, it is important to monitor the levels of CO2 to prevent over-dosing, which can be harmful to fish and other aquatic life.

In summary, Rotala rotundifolia is a beautiful and easy-to-care-for aquarium plant that requires moderate to high lighting conditions, stable water parameters, regular fertilization, and adequate levels of CO2. By following these guidelines, you can successfully cultivate and care for Rotala rotundifolia in your aquarium.

Propagation Methods

Propagating Rotala rotundifolia is a simple process that can be done in a few different ways. Here are some methods that I have found to be effective:

Stem Cuttings

One of the easiest ways to propagate Rotala rotundifolia is through stem cuttings. To do this, I recommend using a pair of sharp scissors to cut the upper portion of the stem (top) of the plant. The cuttings should be at least 10 cm long (4 inches). Then, make a small hole in the plant substrate about 3-4 cm deep and place the stems in the hole and cover with the substrate. Over time, the cuttings will develop roots and new growth will emerge from the stem.

Side Shoots

Another method of propagation is through side shoots. Rotala rotundifolia is known for producing side shoots, which can be removed from the parent plant and replanted in the substrate. To do this, simply remove the side shoot from the parent plant using a sharp pair of scissors or a razor blade. Then, plant the side shoot in the substrate and provide it with adequate light and nutrients.

Division

Finally, Rotala rotundifolia can also be propagated through division. This method involves separating the parent plant into smaller sections and replanting them in the substrate. To do this, carefully remove the parent plant from the substrate and separate it into smaller sections, making sure each section has a healthy root system. Then, replant the sections in the substrate and provide them with adequate light and nutrients.

Overall, propagating Rotala rotundifolia is a straightforward process that can be done using a few different methods. By following these simple steps, you can easily increase the number of Rotala rotundifolia plants in your aquarium and create a beautiful underwater landscape.

Common Uses and Aquascaping

Rotala rotundifolia is a versatile plant that can be used in a variety of ways in aquascaping. As a stem plant, it can be planted in the background or midground of an aquarium, where it will grow upwards and create a lush, green backdrop. It can also be used as a foreground plant, where it will grow in a creeping, bushy manner.

One of the most common uses of Rotala rotundifolia is as a filler plant. Its delicate leaves and stems can fill in gaps between larger plants, creating a seamless and natural-looking aquascape. It can also be used to create contrast, as its bright green color can stand out against darker or redder plants.

In addition to its aesthetic uses, Rotala rotundifolia also provides important benefits to the aquarium ecosystem. It is a fast-growing plant that can absorb excess nutrients from the water, helping to prevent algae growth and improve water quality. It also provides a hiding place for fish and other aquatic creatures, creating a more natural and comfortable environment for them.

When planting Rotala rotundifolia, it is important to provide it with the right conditions for growth. It thrives in high light and CO2 environments, and benefits from regular fertilization. It can also be propagated easily by cutting the stems and replanting them in the substrate.

Overall, Rotala rotundifolia is a valuable and versatile plant that can enhance the beauty and health of any aquarium.