A plant that has become popular among aquarists; Rotala macrandra is heavily desired for its deep red coloration and the aesthetics it brings to an aquascape. It was known to aquarium enthusiasts for decades but has only recently begun to gain widespread attraction due to newer technologies making the cultivation of this plant easier. The plant grows and thrives naturally in marshy areas of India, but is known to require a great deal of care in order to survive inside an aquarium. Needing soft water, nutrient-rich substrates, intense lighting, and carbon dioxide injections.
For the novice aquarist, it can be very demanding to maintain such a plant, but well worth the effort. With the right equipment and care, it can be an easy plant to manage as it grows quickly and can be pruned into many artistic shapes.
What is Rotala Macrandra?
Rotala macrandra is an aquatic plant of the order Myrtales, the family Lythraceae, and the genus Rotala also known as “Giant Red Rotala” or “the king of the reds”. It thrives in the marshes of India but can be found in wetland areas throughout Asia up to Japan. Rotala macrandra has fleshy, ovoid leaves that become green or red depending on whether they are submerged or above water. Submerged leaves grow to around 3-5 cm in length and range from green to red-brown depending on your light levels. Other colors are possible such as pink, tan, and orange, depending on the variant. Originally it was thought to be a red subspecies of Rotala rotundifilia due to their similar above water appearance.
This plant is categorized as an “alternate” leaf arrangement. Meaning the leaves grow on the opposite sides of the stalk, though not necessarily at the same point. Under optimal conditions, the plant will have bushy growth patterns and thick clusters of leaves on many branchlets. Despite the appearance of being a solid wall of plant matter, the leaves are actually very thin and delicate to the point of translucency.
At peak health, the royal red of the leaves mixed with the light green highlights should almost glow in the light of the tank. There will also be tiny oxygen bubbles that form on the leaf tips when healthy and in optimal tank conditions. This is known as “pearling”.
Is Rotala Macrandra Easy to Grow as an Aquarium Plant?
Rotala Macrandra is known as a very picky plant to grow. Especially compared to the more common Rotala rotundifilia. Its leaves are delicate and can break easily with rough handling. For this reason, a plant like this is generally geared more towards an experienced aquarist.
Rotala Macrandra Care
Rotala macrandra, unlike other Rotala in its genus, has many specific requirements that make this plant difficult for a less experienced aquarist to care for. There are a large number of variants of the plant however they all have roughly the same care requirements with some variants (like the red/green types) being only slightly tougher and others (like the variegated and “mini” types) being even more sensitive.
If you maintain the ideal conditions within your tank, Rotala Macrandra can grow very quickly. Averaging about 3 to 4 four inches per week up to as high as 24 inches. Be aware though, that if planted too thickly the higher leaves of your plants can potentially block out light from the lower ones and cause them to die off. It is best to plant your Rotala with about 2 inches of space between the individual stems to allow the light to pass through.
Rotala Macrandra pH
The pH balance of the water should be regulated to between 6.0 to 7.5 as much as possible.
Rotala Macrandra Lighting Requirements
If you desire the red coloration of the leaves you will need to maintain high-intensity lighting within the aquarium. Shadowy and low-light environments will not kill the plant but are extremely sub-optimal. Under low-intensity lighting the leaves will remain green, the growth of the plant will reduce and it will become unhealthy.
Are Aquarium CO2 Injections Necessary to Grow Rotala Macrandra?
For low-light environments, a carbon dioxide injection is recommended, but not necessary. However, in a proper, high-intensity lighting environment the injection is crucial to help produce the vibrant reds in the leaves. Carbon dioxide injections will also help with the overall health of the plant and make it easier to manage in general. Whether you choose to use carbon dioxide or not it is very important to keep the levels consistent as the plant does not take fluctuations in the levels very well. Dips in the levels or inconsistencies can lead to stunting of the tips.
Also of importance to achieving the desired red color is monitoring the nutrient levels in your tank. Iron-rich and slightly acidic substrates are recommended along with a high level of phosphates in the water (1.5 to 2.0 ppm). Be sure to keep nitrates towards the low levels (10 ppm or less). Leaf tips turning orange is a sign of too high a nitrate content, however insufficient nitrate levels can mimic the symptoms of low light levels.
Rotala Macrandra Temperature Requirements
Try to keep the overall temperature somewhere between 72 and 78 degrees Fahrenheit (22 – 26 °C). Any higher than 82 degrees and the plant is likely to turn brown and dissolve in the water.
Compatible Fish Species
It is highly recommended not to place Rotala in the same tank as plant-eating fish unless you want to give them a very expensive meal. The delicate leaves will not survive a lot of abuse from the constant nibbling of fauna.
For example bettas, tetras, pearl gourami, honey gourami, danios, cherry barbs, platies, and guppies all make for excellent choices in a freshwater aquarium that includes these plants. As well as various species of snails and dwarf shrimp.
Be sure to avoid koi fish, goldfish, oscars, rainbow, Jack Dempsey, clown loaches, African cichlids, crayfish, or freshwater crabs as these will either damage your delicate Rotala or find it very tasty.
Propagation and Reproduction
Being a fast-growing plant propagation is most easily accomplished by the use of cuttings. Once the plant starts to become too tall or requires pruning it is best to cut off sections from the parent plant. Aim for cuttings of 4 to 5 inches in length and then replant. Make sure to use an iron-rich fertilizer if you wish to maintain the red color. The parent stalk will grow soon and rapidly as long as optimal conditions are maintained within the tank. If trimmed frequently it will promote shorter, bushier growth.
Can Rotala Macrandra be Grown Emersed?
This species can be grown in emersed or submersed conditions. If emersed it will have a denser structure with the leaves becoming broader and taking on a greener coloration.
Rotala Macrandra Dying and Other Problems
Stunting of Tips and Curling: This is a very common occurrence when growing Rotala macrandra and one where the cause is largely misunderstood. Despite what some people say this is not a result of a lack of fertilization. Typically this is the result of being inconsistent with your carbon dioxide levels. Remember that however much carbon dioxide you decide to use it has to be used consistently over a prolonged period of time. If you are not then the leaf edges and tips will start to crumble, curl and wither.
This can also sometimes be the result of using too much fertilization, not too little. Too little leads to deterioration of the lower leaves, not the tips. So be sure to check both regimens over carefully.
Leaves Turning Pale: Also referred to as Chlorosis, this occurs as a result of an iron deficiency. Meaning the leaves that are ideally supposed to be bright red will instead take on a pale or discolored appearance. Improving the levels of iron in the soil or water column will solve this issue.
Melting: As should be apparent by now, this is a very picky plant. Unstable water parameters like bad temperature or pH balance will cause the plant to melt. Make sure that you strictly and consistently control your water.
Blackened or Browning Bottom Leaves: This is the result of the lower regions of the plant not getting enough light. Usually due to it being blocked by the upper leaves of plants in close proximity. Be sure to give your plants sufficient space. You may need to trim the upper leaves regularly to prevent the lower portions from being blocked.
Because its strong coloration can overwhelm a well-balanced scene, Rotala macrandra is best used sparingly. A light green selection of plants around it and in the background will really help to accentuate its beauty. For this reason, Rotala macrandra is best used as a central focal point or to provide a contrast in the background, especially for some of the smaller varieties.
Rotala Macrandra Types & Variants
There are many types and variants of Rotala Macrandra. Here are some commonly grown types in the aquarium hobby.
Rotala Macrandra Mini
Also known as “Mini Butterfly” this plant is, as the name implies, a smaller version of the traditional Rotala macrandra plant but with a slightly deeper red coloring. All of the rules and requirements for keeping your standard Rotala macrandra healthy and a beautiful red apply to the miniature version as well. High-lighting, carefully monitored carbon dioxide levels, iron and nutrient-rich soils, soft water, and a regulated moderate temperature. Due to the smaller size, this plant looks best in groups, but remember to leave space for the light to reach the bottom leaves.
Rotala Macrandra Green
This is a new variant of Rotala macrandra that produces green leaves as opposed to the standard red and tends to have longer stems.
As with Rotala macrandra red, this plant is a difficult one to care for. Fortunately for this new variant, the requirements are not quite as strict as with the normal variety. The green version can thrive in medium-lit aquariums and has a slightly better tolerance for low pH balances (4.5 to 7). Unlike the original red, the green version potentially grows much taller so it is best used in a larger tank. In regards to placement, this variant is best used as a background plant.
Rotala Macrandra Rose
Often called “Rose Red Rotala” this is an extremely beautiful plant, even by the standards of the other Rotala macrandra variants. Unfortunately, it is also just as vulnerable and delicate as the other variants as well. So all of the guidelines for the main variant apply to this one.
Rotala Macrandra Bangladesh
This decorative variant is offered by a Japanese company called Aqua Design Amano. Though marketed and sold with the name “Bangladesh” there is no record of any plant of this type actually being found there. This plant is sometimes mistaken for a variant of Rotala rotundifilia as opposed to macrandra and has slightly twisted leaves with tones ranging from orange and green to pinkish-red.
This variant is likely the best choice for more novice aquarists as its requirements for care are quite low; especially compared to the other types of macrandra. Any light level is acceptable and you need little in the way of carbon dioxide or other nutrients. However to get the best colors you will need to treat this variant with the same care as all of the others.
Rotala Macrandra Variegated
A much rarer aquatic plant than the standard Rotala. A variegated plant shows two or more differently colored sections. In the case of this plant, the veins lack the common red pigmentation. The whiteness of the venation accents the red magenta/pink coloration and tan orange lines of the leaves. This is one of the hardest of the Rotala macrandras to maintain and is hard to get in North America. Those looking for one may have to import from abroad or purchase clippings from a private seller.
Rotala Macrandra Pearl
A tiny stem plant that is a variant of the “green” and “mini” type of macrandra characterized by short, down-curved leaves and green, pink or purple hues. Like the larger “green” it does not have as strict maintenance requirements as the other types.
Rotala Macrandra Narrow-leaf
Also known as Rotala macrandra “magenta” and Rotala macrandra “Florida” this plant is a mutation that has become one of the most common variants to be sold commercially in the USA. As the name suggests it possesses narrower leaves than others of its kind and a more upright growth habit. Maintenance-wise the narrow leaf is similar to the green variant in terms of what it needs to survive. However, you will need higher lights plus more iron and carbon dioxide if you wish to get the best colors out of your plant.
Rotala Macrandra “Mini Type 2”
Rotala macrandra ‘Mini Type 2’ is a very small-leaved variant of Rotala macrandra. The growth habits of this plant are similar to an emerged plant even though it is cultivated underwater. The leaves can assume different forms; longish-ovoid with a higher middle and the leaf margins turned upwards, or roundish-ovoid.
Where can I find Rotala Macrandra for sale?
Being a very popular and sought-after plant most versions of Rotala macrandra can be found easily in North America. It is easily available in fish stores and nurseries all over the world as well as being sold by many retailers online, including Amazon. Some of the rarer variants, like the variegated, may have to be imported depending on where you live if you can’t find someone willing to sell you some privately. The price varies depending on the place you’re buying from and the exact type of plant you want to purchase, but typically expect to pay between $8.00 to $14.00 US per bunch.
Make sure to get only healthy-looking specimens that have not obviously been clipped.