The Rummy Nose Tetra is a highly popular, peaceful freshwater fish celebrated for its tight, synchronized schooling behaviour and striking colour patterns. Native to the Amazon Basin, they function as an aquatic “canary in a coal mine.” This is because their vibrant red faces quickly fade to translucent white if water quality drops or if they experience stress.

Species Classification:

There are three distinct species commonly sold under the same common name:

• True Rummy-Nose Tetra (Petitella rhodostoma, formerly Hemigrammus rhodostomus): Red coloration stops at the gill covers.
• Brilliant Rummy-Nose/Firehead Tetra (Petitella bleheri): The most common in the aquarium trade, displaying a deeper red that extends past the gills.
• False Rummy-Nose Tetra (Petitella georgiae): Features a narrower red patch and a distinct black line extending down the body spine from the tail.

Quick Care Overview:

• Diet: Omnivorous grazing habits; they thrive on high-quality flakes, micro-pellets, and frozen treats like Daphnia or brine shrimp.
• Social Needs: Strictly schooling; must be kept in groups of at least 6 to 10 fish to ensure security and stimulate natural behaviors.
• Tank Size: Minimum 60 to 70 litres to support their active swimming nature.
• Lifespan: Can live up to 5 to 6 years under optimal conditions.

Ideal Water Parameters:

Rummy Nose Tetras are sensitive, intermediate-level fish that require a mature, fully cycled aquarium. They do not tolerate poor hygiene, ammonia spikes, or highly alkaline water.

• Temperature: 24°C – 28°C
• pH Level: 5.5 – 7.0 (Slightly acidic)
• Water Hardness: 2 – 10 dGH (Soft water)
• Ammonia/Nitrite: Strict 0 ppm

Tank Setup & Compatibility:

• Aquarium Layout: Best kept in heavily planted tanks with dark substrate and driftwood. Leaf litter can be added to introduce natural tannins. Maintain a large open swimming zone in the middle.
• Ideal Tank Mates: Exceptionally peaceful community fish. Excellent companions include other small tetras, Corydoras catfish, Harlequin Rasboras, Bristlenose Plecos, and Dwarf Cichlids
• Fish to Avoid: Large or aggressive species that might view their slender 5 cm bodies as food (such as fully grown Angelfish or large predatory catfish).