Killifish / Fundulopanchax gardneri – How to Hatch & Breed Steel Blue Killifish
Fundulopanchax gardneri (Steel Blue Killifish) is one of the best beginner-friendly killifish — hardy, productive, and beautifully colored.
Native range includes:
- Nigeria
- Cameroon
Specifically from river systems in southeastern Nigeria and western Cameroon.
Temperament – Peaceful? Not Always.
Although often described as peaceful, this species can be:
- Highly dominant
- Aggressive between males
- Rough on females (especially young ones)
In community tanks:
- Some strains behave well
- Others may harass or kill weaker fish
Male-to-male aggression can be intense. If keeping multiple males:
- Keep 3–4 males minimum in larger tanks
- Or just keep one male per breeding setup
Size & Lifespan
- Males: 6–8 cm (sometimes larger)
- Females: about half the size
- Lifespan: 5+ years (long for a killifish)
Breeding Style – “Switch Spawner”
This species is known as a switch spawner, meaning it can:
- Lay eggs in spawning mops
- Lay eggs in peat
- Lay eggs among floating plants
However, the common steel blue strain strongly prefers mops.
Even within mops, different pairs may lay:
- At the top
- At the bottom
- All through the strands
Best Breeding Setup
For beginners:
- 1 male + 2–3 females
- Small tank (30 x 20 x 20 cm works)
- Sponge filter
- No heater required if room temp stable
- Ideal breeding temp: ~23°C
To maximise egg production:
- Keep males and females separate.
- Condition them well on live food.
- Introduce female when plump.
- Allow spawning for a few days.
- Remove female to rest.
This reduces stress and extends female lifespan.
Water Conditions
Very adaptable species.
- pH: 6.0 – 7.5
- Ideal breeding pH: ~6.5
- Hardness: around 6 dGH preferred
- Weekly water changes (up to 1/3)
- Tap water usually fine
- No special lighting required
They tolerate both soft and moderately hard water.
Egg Collection & Incubation
Eggs are large (~1 mm), easy to spot.
You can collect:
- Up to 30 eggs per female per day
Important:
- Collect eggs daily
- Adults will eat them
Incubation time:
- In water (mop incubation): 2–3 weeks
- On damp peat: 3–4 weeks
Fry Care
Fry are small but not tiny.
You can feed immediately:
- Baby brine shrimp
- Microworms
No infusoria required.
Keep:
- Water shallow initially
- Raise water level gradually as fry grow
Feed at least twice daily.
Small water changes every 2–3 days help growth.
Growth & Sexing
- Rapid growth
- Sexing visible at 5–6 weeks
- Ready to breed at ~3 months
Separate larger fry from smaller ones to prevent predation.
Disease Warning
Velvet is a common issue in fry.
Prevention:
- Add ½ to 1 teaspoon salt per 4 litres
- Maintain stable water
- Avoid sudden large water changes
Adults also tolerate light salt additions.
Key Breeding Tips
- Start with 1 male to 2–3 females
- Feed live food for best egg output
- Use mops for best results
- Remove females after a few days
- Collect eggs daily
- Keep fry water stable and shallow
Final Thoughts
Fundulopanchax gardneri is:
- Hardy
- Productive
- Long-lived
- Beginner-friendly
- Extremely colorful (many morphs: blue, green, etc.)
If someone wants to start breeding killifish, this is one of the safest and most rewarding species to begin with.
Just remember — the males may be small, but they definitely have attitude.
