Community Fish Spotlight: Blue Gardner’s Killifish (Fundulopanchax gardneri)

A Spark of Color, a Splash of Personality — Is This Peaceful Oddball Right for You?

If you’ve been looking to add a true showpiece to your tank — something bold, interactive, and full of charm — the Blue Gardner’s Killifish, also called the Steel Blue Killifish, might be the perfect fit. Known for its shimmering coloration and unique behavior, this small but mighty fish makes a big impression in planted or nano-style aquariums.

Why Hobbyists Love This Fish

Tank-bred and beginner-friendly, this variety of Fundulopanchax gardneri is a favorite among aquarists who want something a little different. Males sport electric blue bodies with red markings and a splash of attitude, while females offer a more subtle beauty and help balance out tank dynamics.

These fish are non-annual killifish, meaning they don’t require any seasonal dry periods to breed — a major plus for aquarists who want to try their hand at natural spawning without complex setups.

Life Cycle & Breeding Behavior

Unlike some wild killifish that live fast and die young, tank-bred Gardner’s Killifish have a manageable 2–3 year lifespan. They mature quickly — often within 2 months — and are eager spawners once conditions are right.

Spawning is simple: just provide fine-leaved plants or a spawning mop. The eggs are scattered and typically hatch within 10–14 days if collected and raised in stable conditions. While they will spawn in a community tank, fry survival is low without separation, so plan ahead if you want to raise a new generation.

How to Tell Males and Females Apart

Sexing this species is straightforward, especially once the fish are fully colored. Males are bold and brightly patterned, while females are smaller and more subdued. Here's a quick breakdown:

Tank Setup Tips

These fish may be small, but they appreciate thoughtful aquascaping. A well-planted tank with floating cover helps them feel secure and brings out natural behaviors. Soft, slightly acidic water is ideal, and they prefer slower flow to mimic the calm pools they come from in the wild.

• Tank Size: 10 gallons minimum

• Temperature: 72–78°F (22–25.5°C)

• pH: 6.5–7.5

• KH: 4–10

• Diet: Omnivorous — accepts flake, micro pellets, frozen daphnia, baby brine shrimp

• Social Behavior: Best in pairs or trios (1 male to 2 females)

• Lifespan: 2–3 years

Final Thoughts

The Blue Gardner’s Killifish is more than just eye candy — it’s a personality-packed species that brings beauty and intrigue to smaller aquariums. Easy to feed, fun to watch, and a joy to breed, this fish checks a lot of boxes for aquarists who want something peaceful, colorful, and just a little quirky.

If your tank setup checks the boxes, it might be time to give this standout species a home.

Q&A: Blue Gardner’s Killifish

Q: Are Blue Gardner’s Killifish aggressive?
A: No — they are generally peaceful, though males can be territorial with each other. They’re best kept in trios (1 male, 2 females) or species-only tanks.

Q: Do they need a lid on the tank?
A: Yes! Killifish are excellent jumpers. A tight-fitting lid is essential to keep them safe.

Q: How big do they get?
A: Adult males typically reach about 2.5 inches, while females stay slightly smaller.

Q: Can they live with shrimp?
A: They may snack on very small shrimp or shrimplets, but larger Neocaridina or Amano shrimp are generally safe with plenty of hiding spaces.

Q: How long do they live?
A: Tank-bred Blue Gardner’s Killifish live about 2–3 years on average.

Q: Will they breed in a community tank?
A: Yes, but the eggs and fry are unlikely to survive unless you remove them or provide dense cover.

Q: Are they hard to keep?
A: Not at all! They're hardy and adaptable — just provide stable water parameters and a peaceful tank environment.

Q: What do they eat?
A: They’ll thrive on high-quality flakes, micro pellets, and frozen or live foods like baby brine shrimp and daphnia.

Q: Do males and females look different?
A: Yes — males are vividly colored with long fins; females are smaller, more muted, and rounder-bodied.

Q: Can I keep more than one male together?
A: Only in larger tanks (15+ gallons) with lots of hiding spots. Otherwise, stick to one male per group to avoid aggression.