Overview
Rotala rotundifolia is one of the most popular stem plants, forming dense, feathery bushes whose tops blush pink to fiery orange-red under bright light. It grows fast and responds dramatically to how you light and dose the tank.
It is easy to grow green, but getting the vivid red colour takes strong light, CO2, and a lean nitrate / rich iron approach.
| Difficulty | Easy-medium |
| Light | Medium-high |
| CO2 | Recommended for red/bushy |
| Growth rate | Fast |
| Placement | Background |
| Max height | 12-24 in (30-60 cm) |
| Feeding | Water column + roots |
| Temperature | 72-82°F (22-28°C) |
| Propagation | Cuttings (topping) |
Light & CO2
Green growth is easy under medium light with no CO2. For the bushy, red-topped look, provide high light and pressurised CO2 , the intense light and good nutrients trigger the red pigments.
Planting & placement
Plant individual stems a few centimetres apart at the back; they root quickly and grow upward. As they fill in they form a hedge that you shape by trimming.
Feeding & growth
A fast grower that draws nutrients from both water and substrate. Rich iron and micros deepen the red; very high nitrate tends to keep it green. Trim (top) the stems and replant the healthy tops to build density.
Propagation
Cut the top few inches off a healthy stem and push it into the substrate , it roots and grows a new plant, while the cut base sends out side shoots and becomes bushier.
Common problems
Leggy, pale, or dropping lower leaves usually mean too little light reaching the base , trim and replant tops, and increase light or thin the stand. Stunted tips point to a CO2 or micro-nutrient shortfall.
Fun facts
- Rotala's tops turn pink to fiery red under high light and CO2 , it stays green in low tech.
- You make it bushier by 'topping': cut and replant the tops, and the base branches out.
- It is one of the fastest-growing popular stem plants.
- Lean nitrate with plenty of iron pushes the reds; high nitrate keeps it green.
- A single stem can become a whole hedge within weeks.
Frequently asked questions
How do you make Rotala turn red?
Strong light and pressurised CO2 are the main drivers, combined with plenty of iron/micros and leaner nitrate. Under low light without CO2 it grows green.
Does Rotala rotundifolia need CO2?
Not to survive , it grows green without it. CO2 (plus high light) is what produces the dense, bushy, red-topped growth people want.
How do you make Rotala bushy?
Trim the tops ('topping') and replant them. Cutting the stem makes the base send out multiple side shoots, thickening the stand over time.
Why are the lower leaves of my Rotala falling off?
Usually too little light reaches the shaded base as the stand thickens. Thin and trim it, replant the healthy tops, and improve light penetration.
Is Rotala good for beginners?
Yes for green growth , it is fast and forgiving. Achieving the vivid red colour is the more advanced, high-tech goal.
