Royal Tetra (Inpaichthys kerri)

Regal, iridescent, and strikingly beautiful — the Royal Tetra (Inpaichthys kerri) is a gem of the tetra world, often mistaken for the Emperor Tetra but with its own unique charm. Males display a stunning royal blue iridescent stripe along the body, contrasted by warm golden-brown tones and vivid blue-tipped fins. A peaceful, elegant schooling fish that elevates any planted or community aquarium.

Overview

Appearance

Males are the showstoppers — displaying a broad, iridescent royal blue stripe running from the snout to the tail, set against a warm golden-brown body. Their dorsal fin is tipped with vivid blue, and their overall colouration intensifies when in good condition or displaying to females. Females are more subdued with a purple-toned stripe, but equally attractive in a mixed school. Together, a group of Royal Tetras creates a shimmering, jewel-toned display.

Water Parameters & Tank Setup

• Temperature: 73 – 81°F (23 – 27°C)
• pH: 5.5 – 7.0 (soft, slightly acidic water preferred)
• General Hardness (GH): 1 – 10 dGH
• Tank Size: Minimum 20 gallons for a school of 8+
• Lighting: Low to moderate — their iridescent blue stripe shines beautifully under subdued lighting
• Substrate: Dark substrate enhances their colouration
• Plants & Decor: Densely planted tanks with open swimming space; driftwood and leaf litter add a natural Amazonian feel

Diet & Feeding

• Staple: High-quality flake food or micro pellets
• Treats: Frozen bloodworms, brine shrimp, daphnia, and micro worms

Feed small amounts 2–3 times daily.

Compatibility & Tank Mates

Best kept in groups of 8 or more. Ideal tank mates include:

• Other small, peaceful tetras and rasboras
• Corydoras catfish
• Dwarf cichlids (Apistogramma)
• Dwarf shrimp (generally safe with adults)

Avoid housing with large or aggressive fish.

Breeding

Royal Tetras are egg scatterers. They spawn among fine-leaved plants in a well-conditioned aquarium. A separate breeding tank is recommended as parents will eat eggs. Eggs hatch in 24–48 hours and fry can be fed infusoria or liquid fry food initially.

The Royal Tetra is a truly regal fish — peaceful, beautiful, and easy to keep. Add a school to your planted aquarium and enjoy the royal blue shimmer they bring to every corner of the tank.