JAPANESE BLUE MOSAIC GUPPY | POECILIA RETICULATUS

The Japanese Blue Mosaic Guppy (Poecilia reticulata) is a breathtakingly beautiful and refined guppy variety known for its radiant blue tones and intricate mosaic tail pattern. Originating from selective breeding in Japan, this strain combines elegance and color depth, featuring a shimmering light-to-deep blue body that transitions into a tail covered with delicate, lace-like spots and streaks in shades of blue, black, and sometimes white. The result is a truly mesmerizing display of motion and color that stands out in any aquarium.

Adult males typically grow to about 1.5 inches (3.5–4 cm) and show the most intense coloration and patterning, while females reach up to 2.5 inches (6 cm) and exhibit softer tones. The males’ tails fan out widely as they swim, showing off their mosaic patterns with every flick of motion.

Ideal water parameters:
Temperature: 72–82°F (22–28°C)
pH: 7.0–8.0
Hardness: 8–20 dGH

Tank setup: Japanese Blue Mosaic Guppies thrive in clean, well-filtered aquariums of 10 gallons or larger with moderate lighting and stable water conditions. Dark substrates or backgrounds enhance their iridescent blue coloration. Provide live or artificial plants such as Java Moss, Hornwort, or Anubias for cover and breeding areas. Because they are livebearers, females give birth to fully developed fry every 4–6 weeks, and dense plant cover helps protect the young.

Diet: These guppies are omnivorous and thrive on a balanced, varied diet. Offer high-quality flakes or micro-pellets as a staple, with regular feedings of frozen or live foods such as brine shrimp, daphnia, and bloodworms. Vegetable-based foods like spirulina flakes or blanched spinach promote vibrant coloration and long-term health.

Temperament and tankmates: Japanese Blue Mosaic Guppies are peaceful, active, and social fish that enjoy the company of their own kind and other gentle community species. Ideal tankmates include platies, mollies, endlers, tetras, rasboras, and corydoras. Avoid fin-nipping or aggressive fish that might damage their ornate tails.

In summary, the Japanese Blue Mosaic Guppy is a graceful and highly ornamental fish that adds both color and sophistication to any freshwater aquarium. Its glowing blue hues, intricate tail pattern, and calm temperament make it a standout choice for aquarists who appreciate beauty, harmony, and elegance in motion.