Rotala robustus ‘mini’ aka. Rotala indica ‘robustus’, Dwarf Indian Toothcup
Difficulty: Moderately difficult to challenging
Size: Short and dense; will rarely exceed 10cm in height
Native Range: Southeast Asia, Eastern and Southern China
Position and Usage: Foreground to midground
Growth Rate: Slow
Lighting: 3/5 – 4/5
Water Conditions: 20-28°C; softer water and lower to neutral pH preferred
Propagation: Make stem cuttings of several nodes each, taken from new growth, and replant
Special Requirements: Micronutrient rich substrate; iron supplementation
Rotala robustus 'Mini' (Ammania bonsai)
Rotala Robustus ‘Mini’ is a low-growing, naturally bushy species well-suited to foreground and midground placement in aquaria of all sizes. This stem plant looks stunning when planted around hardscape, establishing driftwood and rocks as natural parts of the aquatic environment. Under ideal conditions, Rotala ‘Mini’ will send out horizontal stems, enabling it to spread laterally across the substrate. It does require high lighting, and so taller, midground specimens should be kept under careful supervision so as not to shade this plant. This species grows slowly, making it prone to algal growth. Low-temperatures are well-tolerated but may slow growth even further. We recommend both CO2 injection and circulation to promote growth and dispel algae. Unlike most stem plants, Rotala ‘Mini’ is relatively unresponsive to water column fertilization and is primarily a root feeder. Thus, we recommend a rich substrate with abundant micronutrients, most especially iron. Root capsules may be placed beneath the plant to provide a slow-release source of nutrients.
Do not plant this species in tanks with large fish or herbivorous inhabitants, as its stems are brittle and easily damaged.