Rotala Blood Red Care Guide: Deepest Red Stem Plant

Rotala Blood Red (often sold as Rotala sp. ‘Blood Red’ or Rotala macrandra ‘Mini Type 4’) produces some of the most intensely red colouration achievable in a planted aquarium. When grown in optimal conditions, its leaves glow a deep crimson that makes every other red plant look pale by comparison. This Rotala Blood Red care guide from Gensou Aquascaping at 5 Everton Park is for aquascapers chasing the ultimate red.

Plant Overview

Rotala Blood Red is a cultivated variant in the Rotala macrandra group, selected for its exceptionally deep red pigmentation. It grows as a fine-leaved stem plant reaching 15–30 cm, with small, rounded leaves densely packed along the stem. Under optimal conditions, the entire plant — stems, leaves and new growth — turns a uniform deep red to burgundy. It is considered a moderate to advanced difficulty plant.

Light Requirements

This plant demands high to very high lighting — 100+ PAR at substrate level is the starting point for true red colouration. Under moderate light, it grows but stays orange or pinkish, never achieving the deep blood red that gives it its name. Position it directly under the brightest part of your light. Many successful growers use dual LED fixtures or supplementary red-spectrum lighting to push colour intensity further.

CO2 Requirements

CO2 injection is non-negotiable. Maintain 25–35 ppm consistently throughout the photoperiod. Fluctuating CO2 levels cause inconsistent colour and growth. Use a quality drop checker positioned near the plant to monitor levels. Without pressurised CO2, this plant will not achieve its potential and may slowly decline.

Nutrient Demands

Iron is the single most important nutrient for red colouration. Dose a chelated iron supplement (DTPA or EDDHA form) at two to three times the standard recommended rate. Some growers dose iron daily rather than two to three times per week. Nitrate should be maintained at moderate levels (5–15 ppm) — too high and the plant shifts toward orange; too low and growth stalls. Phosphate and potassium should be dosed consistently per your chosen fertiliser regimen (EI or lean dosing).

Planting and Growth

Plant stems in tight groups of seven to ten in the midground or background. Space stems 1–2 cm apart for a dense bush effect. Growth is moderate — expect 3–5 cm per week under optimal conditions. The plant grows upward and slightly outward, creating a full, rounded bush shape when topped regularly. New growth at the top shows the deepest colour, while shaded lower leaves may turn green or shed.

Pruning

Regular topping every one to two weeks is essential. Cut the top 10 cm and replant — the cut stumps produce two side shoots each, gradually building a dense, bushy stand. Discard lower stem sections that have lost leaves. The constant topping-and-replanting cycle keeps the display fresh and maximises the proportion of intensely coloured new growth visible to the viewer.

Common Issues

Orange or pink instead of red: light intensity or iron dosing is insufficient — increase both. Melting stems: usually caused by sudden parameter changes or transplant shock — maintain stability. Green lower leaves: normal, as shaded portions cannot maintain red pigmentation. Algae on leaves: typically indicates CO2 or nutrient imbalance — adjust before the algae smothers the fine leaves. This is a demanding plant, but the reward of a perfectly grown Blood Red bush is one of the most visually stunning sights in planted aquariums.

Related Reading

• Cryptocoryne Wendtii Red Care Guide: Deep Bronze in Low Light
• How to Dose Iron for Red Aquarium Plants: Chelated vs Gluconate
• How to Grow Alternanthera Reineckii Bright Red: Iron and Light
• How to Grow Red Aquarium Plants: Light, Iron and CO2
• How to Grow Rotala Rotundifolia Bushy: Trimming and Light Tips