TankBud

One species · 2 forms

Rotala ramosior

Also known as Lowland Rotala, Toothcup, Ammannia ramosior

FreshwaterStemCuttingsSide shoots

Care at a glance

Light
High light
CO2
CO₂ required
Temperature
64–86°F
18–30°C
Max height
15.7 in
40 cm
Growth rate
Medium
Placement
Background
Type
Stem
pH
4.5–7.0
Hardness
0–8 dGH
Spread
2 in (5 cm)
Nutrient uptake
Root + water column
Growth region
Submersed or emersed
Difficulty
Difficult
Family
Lythraceae
Origin
North America (USA, Canada, Mexico)

Pick a form

Sunset and Florida both need the strong light, injected CO2 and steady feeding of plain Rotala ramosior.

Overview

Rotala ramosior is a demanding, light-hungry stem plant for the background. Its colors are subtle, so it is grown for its fine, upright form and as contrast against red or feathery plants.

Did you know

Rotala ramosior is one of the most demanding plants in the hobby. Yet in the wild it is a native wetland plant that tolerates everything from Ontario cold to the Deep South.

Caring for Rotala ramosior

Plant Rotala ramosior as single stems in the background. It is amphibious, and emersed plants convert to submersed growth fairly easily.

It wants strong light, injected CO2 and a steady supply of both macro and micro nutrients. Feeding the substrate with root tabs is a plus. It handles 64 to 86°F (18 to 30°C) and a pH of 4.5 to 7.

It grows at a medium pace and propagates slowly. Take the tops high up and the stump puts out a few side shoots, but stumps cut low usually die.

Sunset and Florida are forms of Rotala ramosior, a wetland plant native across the Americas. Sunset grows shoots 4 to 5 cm wide, with leaves 2.5 to 3 cm long in orange to brown-red. Florida is smaller, with purple leaves 1 to 1.3 cm long on shoots about 2.5 cm wide. Both forms keep a light green stem and midrib. Plain Rotala ramosior grows green underwater.

Florida is a wild collection. US hobbyists gathered it with special permission at Corkscrew Swamp Sanctuary in Florida and shared it on US plant forums in 2013. Sunset has no recorded origin. Flowgrow and Aquasabi place it in Rotala ramosior, and it has also sold as Ammannia sp. 'Sulawesi'. Aquasabi grew both in its tanks, where Sunset gained 10 to 11 cm a month and Florida about 9 cm.

Good to know

Rotala ramosior is in the family Lythraceae, and the common names Lowland Rotala and Toothcup both refer to it. It has been treated in the past under Ammannia. Where it escaped cultivation in Taiwan, it has become invasive.

In the wild

Unlike most aquarium rotalas, Rotala ramosior is native to North America. Its range covers most of the continental United States plus parts of Canada (British Columbia and Ontario), Mexico and the West Indies. It grows in full sun on wet ground, pond margins and shallow water, both above and below the surface. In its native range it is a declining plant rather than a weed. Several US states, such as Minnesota, protect it as threatened or endangered, though it is not regulated or restricted for aquarium keeping.

Common questions

Is Rotala Florida Sunset the same plant as Rotala Sunset?

Rotala Florida Sunset is a shop label that blends the names of the two forms. Shops use it for either plant, so check the photo before you buy. Rotala Florida has small purple leaves, 1 to 1.3 cm long. Rotala Sunset has longer leaves, 2.5 to 3 cm, in orange to brown-red.

Why is my Rotala Florida losing its lower leaves?

Low CO2 or low calcium often makes the lower stem of Rotala Florida rot and shed its leaves. The 2Hr Aquarist suggests CO2 above 35 ppm and a GH of about 4 to 6. Its hard water guide says Rotala Sunset also prefers a slightly raised GH.

Does Rotala ramosior need to be planted in the substrate?

Yes. Strip the leaves from the lower part of each stem, then push the stems into the substrate one at a time, a little apart.

Does Rotala ramosior need CO2?

Yes. Rotala ramosior needs injected CO2 to grow well, and it usually struggles without it.

How much light does Rotala ramosior need?

Rotala ramosior needs high light from a strong planted-tank LED. In weaker light its stems stretch and drop their lower leaves.

Does Rotala ramosior need root tabs?

They help. Rotala ramosior takes nutrients through both its roots and its leaves. Root tabs near its roots and a liquid fertilizer cover both.

How do you propagate Rotala ramosior?

Rotala ramosior propagates by cuttings and side shoots. Cut off the top of a stem and replant it, and the stump left behind grows new shoots. Cut a side shoot off once it has a few leaves and plant it on its own.

How tall does Rotala ramosior grow?

Rotala ramosior grows to about 15.7 in (40 cm) tall. It grows at a moderate pace.

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