Alternanthera Cardinalis

Description

**Alternanthera cardinalis**, also known as **Cardinal Red Alternanthera** or **Cardinal Plant**, is a beautiful aquatic plant popular in freshwater aquariums due to its striking red and green coloration. Here’s a comprehensive care guide to help you maintain this plant in your aquarium:

### 1. **Lighting:**

– **Intensity**: Alternanthera cardinalis thrives under **high lighting** conditions. Provide at least **2 to 3 watts per gallon** of light. Strong light will help the plant maintain its vibrant red color.

– **Light Spectrum**: Opt for full-spectrum or light in the range of **6500K to 10000K** to ensure healthy growth and optimal coloration.

– **Duration**: Aim for about **8 to 10 hours** of light per day to avoid algae growth and promote proper plant growth.

### 2. **Water Conditions:**

– **Temperature**: Maintain a water temperature between **72°F and 82°F (22°C to 28°C)**. This plant prefers warmer water but can tolerate a range of temperatures.

– **pH Level**: A pH range of **6.0 to 7.5** is ideal for the Cardinal Plant. Slightly acidic to neutral water is best.

– **Hardness**: Soft to medium water hardness (4-12 dGH) is recommended for this plant.

– **Water Movement**: A moderate water flow is ideal, as this plant doesn’t do well with strong currents that can damage its delicate leaves.

### 3. **Substrate:**

– Use a **nutrient-rich substrate**, such as **aquatic soil** or **fine gravel** that can hold fertilizers. Alternanthera cardinalis benefits from a nutrient-rich environment, especially when planted directly in the substrate.

– Adding **root tabs** or liquid fertilizers is a good idea to ensure the plant receives sufficient nutrients.

### 4. **Fertilization:**

– Alternanthera cardinalis has a **high nutrient demand**. Use a combination of **liquid fertilizers** (containing trace elements, potassium, nitrogen, and phosphorus) and **root tabs** for optimal growth.

– Regular dosing of **iron** supplements is also important, as it helps the plant maintain its rich red coloration.

### 5. **CO2 Supplementation:**

– **CO2 injection** is highly beneficial and often recommended for this plant. It promotes healthier growth and more intense coloration, especially in a high-light aquarium.

– If you don’t have CO2 supplementation, it can still grow, but you may see slower growth and less vibrant color.

### 6. **Growth and Pruning:**

– **Alternanthera cardinalis** grows **vertically**, reaching heights of 12 to 24 inches (30 to 60 cm), making it suitable for the background of a tank.

– To encourage bushier growth and prevent the plant from getting too tall, regularly trim the top shoots. This will also help to maintain its appearance and promote new side shoots.

– Remove any dead or decaying leaves to keep the plant healthy and prevent algae growth.

### 7. **Tankmates:**

– This plant is generally compatible with most peaceful **freshwater aquarium species**. It’s often used in planted aquariums with fish such as **Tetras**, **Guppies**, **Corydoras**, and **Neons**.

– Avoid fish that may uproot or eat the plant, such as **Goldfish** or **Cichlids**.

### 8. **Common Problems:**

– **Yellowing Leaves**: This could be a sign of nutrient deficiency, often due to a lack of iron, nitrogen, or potassium. Ensure regular fertilization and CO2 injection.

– **Leggy Growth**: If the plant becomes too tall with sparse leaves at the bottom, it’s often due to insufficient light. Increase the light intensity or duration to encourage denser growth.

### 9. **Propagation:**

– **Alternanthera cardinalis** can be propagated by cutting the top portion of the plant and replanting it in the substrate. The cuttings will grow roots and develop into new plants.

– Ensure the new plants have sufficient light and nutrients to grow properly.

By maintaining the right conditions—strong lighting, nutrient-rich water, and CO2 supplementation—Alternanthera cardinalis can thrive, offering a stunning red accent in your aquarium.