Scratched INPA Tetra (3cm) refers to Inpaichthys kerri, commonly known as the Blue Emperor Tetra. The term “scratched” typically describes individuals showing irregular scale shine or light pattern breaks along the metallic blue body.

At 3cm, these are healthy juveniles approaching sub-adult size, already displaying their signature iridescent blue sheen.

🌿 Species Overview

• Scientific Name: Inpaichthys kerri

• Common Name: Blue Emperor / INPA Tetra

• Current Size: ~3 cm

• Adult Size: 4–5 cm

• Origin: Brazil (Aripuanã River Basin)

• Temperament: Peaceful, active schooling fish

The species was named after INPA (Brazil’s National Institute of Amazonian Research).

🎨 Appearance

• Metallic blue to violet body coloration

• Dark horizontal lateral stripe

• Transparent to lightly tinted fins

• “Scratched” effect may show uneven reflective scaling

• Strong shimmer under planted-tank lighting

Color deepens significantly in mature males.

🐟 Behavior & Compatibility

• Keep in groups of 6–10 or more

• Peaceful but energetic mid-water swimmers

• Compatible with rasboras, small barbs, Corydoras, dwarf cichlids

• Avoid large predators

They look best in coordinated schools within planted aquariums.

💧 Ideal Water Parameters

• Temperature: 23–27°C

• pH: 5.5–7.0

• Hardness: Soft to moderately soft

• Water Flow: Gentle to moderate

Stable water conditions enhance coloration and reduce stress.

🏡 Tank Setup

• Minimum Tank Size: 60–80 liters

• Planted tank recommended

• Dark substrate enhances blue shimmer

• Moderate lighting

• Open mid-water swimming space

They thrive in Amazon-style aquascapes.

🍽 Feeding

• High-quality micro pellets or flakes

• Frozen daphnia, brine shrimp

• Occasional live foods

Feed 1–2 small meals daily.

📈 Care Level

• Difficulty: Easy

• Hardy and adaptable

• Suitable for community aquariums

🌟 Why Choose 3cm Scratched INPA Tetra?

• Metallic blue shimmer

• Active schooling behavior

• Hardy and community-friendly

• Ideal for planted aquariums

• Great contrast against green aquascapes

INPA Tetras bring cool-toned metallic blue movement to planted tanks, especially striking when kept in coordinated groups.