Can Forktail Blue-eye and Julii Corydoras (False Julii) Live Together?

🟢Ideal Tank Mates

Yes, Forktail Blue-eye and Julii Corydoras (False Julii) are ideal tank mates. Both species share compatible water parameters and peaceful temperaments, making them well-suited for a community aquarium. They occupy different areas of the water column, which reduces competition for space. A minimum tank size of 72 litres is recommended.


At a Glance

Forktail Blue-eye

Pseudomugil furcatus

Julii Corydoras (False Julii)

Corydoras trilineatus

🐠Family Group
Forktail Blue-eye
Rainbowfish
Julii Corydoras (False Julii)
Catfish
Temperament
Forktail Blue-eye
Peaceful (2/10)
Julii Corydoras (False Julii)
Peaceful (0/10)
Temperature
✓ Compatible
Forktail Blue-eye
24–28°C
Julii Corydoras (False Julii)
22–26°C
pH Range
✓ Compatible
Forktail Blue-eye
7–8
Julii Corydoras (False Julii)
6–7.5
Hardness (dGH)
✓ Compatible
Forktail Blue-eye
5–15
Julii Corydoras (False Julii)
2–15
Water Type
✓ Compatible
Forktail Blue-eye
Freshwater Only
Julii Corydoras (False Julii)
Freshwater Only
Flow Preference
✓ Compatible
Forktail Blue-eye
Moderate
Julii Corydoras (False Julii)
Moderate
Min Tank Volume
Combined: 72 L
Forktail Blue-eye
55 L
Julii Corydoras (False Julii)
60 L
Swimming Level
✓ Different zones
Forktail Blue-eye
TopMiddle
Julii Corydoras (False Julii)
Bottom
🏷️Behavior Tags
Forktail Blue-eye
Nano / Bite-sized (Predation Risk)Hyperactive / Fast SwimmerJumper (Lid Required)
Julii Corydoras (False Julii)
Hyperactive / Fast Swimmer

Behaviour & Temperament

Forktail Blue-eye is a peaceful species (2/10), while Julii Corydoras (False Julii) is peaceful (0/10). This modest difference means Forktail Blue-eye may occasionally assert dominance over Julii Corydoras (False Julii).

In terms of spatial distribution, Forktail Blue-eye prefers the Top (Surface) and Middle (Open Water) zones, whereas Julii Corydoras (False Julii) occupies the Bottom (Substrate) zone. Because they use different levels of the water column, territorial disputes are less likely and the tank will appear more balanced.

Worth noting: Forktail Blue-eye is a known jumper, so a tight-fitting lid is essential.

Water Parameters

The safe temperature window for both species falls between 24°C and 26°C. Aim for the midpoint of this range (around 25.0°C) for optimal comfort.

Both fish can tolerate a pH between 7 and 7.5. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 5–15 dGH. Regular testing will ensure conditions stay within this range. An aquarium test kit is recommended for monitoring.

Tank Setup

To house Forktail Blue-eye and Julii Corydoras (False Julii) together, plan for an aquarium of at least 72 litres with a minimum length of 60 cm. This accounts for the larger species' space requirements with an additional 20 % buffer to reduce territorial tension.

Providing a mix of open swimming space and sheltered areas with rocks, driftwood, or plants will keep both species comfortable and allow natural behaviour.

Specific environmental needs for this combination include: Plants - Densely covered, Sand (Sifters). Meeting these requirements will help both species thrive.

Both species do well with moderate (standard) water movement, so a standard filtration setup rated for the tank volume should suffice.

Find the right tank equipment

Browse tanks, décor, and equipment suited for this setup.

Frequently Asked Questions

Can Forktail Blue-eye and Julii Corydoras (False Julii) live together?

Yes. Forktail Blue-eye and Julii Corydoras (False Julii) are considered ideal tank mates. Their water parameters, temperaments, and behaviour profiles are well matched for a community aquarium.

What size tank do Forktail Blue-eye and Julii Corydoras (False Julii) need?

A minimum of 72 litres (tank length at least 60 cm) is recommended. This provides enough space for both species to establish their own areas and reduces the likelihood of territorial disputes.

What water temperature is best for Forktail Blue-eye and Julii Corydoras (False Julii) together?

Keep the aquarium between 24°C and 26°C. A target of around 25.0°C sits comfortably within both species' preferred ranges.

Are Forktail Blue-eye or Julii Corydoras (False Julii) aggressive?

Forktail Blue-eye is peaceful (2/10) and Julii Corydoras (False Julii) is peaceful (0/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Forktail Blue-eye and Julii Corydoras (False Julii) need?

Both species overlap in the 7–7.5 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.


Related Comparisons

Forktail Blue-eye & Boeseman's Rainbowfish

·

🟢Ideal Tank Mates
Forktail Blue-eye: PeacefulBoeseman's Rainbowfish: Peaceful

Forktail Blue-eye & Dwarf Neon Rainbowfish (Praecox)

·

🟢Ideal Tank Mates
Forktail Blue-eye: PeacefulDwarf Neon Rainbowfish (Praecox): Peaceful

Forktail Blue-eye & Gertrude's Spotted Blue-eye

·

🟢Ideal Tank Mates
Forktail Blue-eye: PeacefulGertrude's Spotted Blue-eye: Peaceful

Forktail Blue-eye & Red Rainbowfish

·

🟢Ideal Tank Mates
Forktail Blue-eye: PeacefulRed Rainbowfish: Peaceful

Forktail Blue-eye & Turquoise Rainbowfish

·

🟢Ideal Tank Mates
Forktail Blue-eye: PeacefulTurquoise Rainbowfish: Peaceful

Forktail Blue-eye & Celebes Rainbowfish

·

🟢Ideal Tank Mates
Forktail Blue-eye: PeacefulCelebes Rainbowfish: Peaceful

Julii Corydoras (False Julii) & Bristlenose Pleco

·

🟢Ideal Tank Mates
Julii Corydoras (False Julii): PeacefulBristlenose Pleco: Peaceful

Julii Corydoras (False Julii) & Bronze Corydoras

·

🟢Ideal Tank Mates
Julii Corydoras (False Julii): PeacefulBronze Corydoras: Peaceful

Julii Corydoras (False Julii) & Otocinclus

·

🟡Possible with Caution
Julii Corydoras (False Julii): PeacefulOtocinclus: Peaceful

Julii Corydoras (False Julii) & Panda Corydoras

·

🟢Ideal Tank Mates
Julii Corydoras (False Julii): PeacefulPanda Corydoras: Peaceful

Julii Corydoras (False Julii) & Peppered Corydoras

·

🟢Ideal Tank Mates
Julii Corydoras (False Julii): PeacefulPeppered Corydoras: Peaceful

Julii Corydoras (False Julii) & Pygmy Corydoras

·

🟡Possible with Caution
Julii Corydoras (False Julii): PeacefulPygmy Corydoras: Peaceful