Can Blue Back Blue Eye and False Glass Catfish Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 4, 2026
Not Recommended

Blue Back Blue Eye and False Glass Catfish are not recommended as tank mates due to incompatible water types and incompatible hardness ranges. Housing these species together is likely to result in stress, health problems, or direct harm to one or both fish.


At a Glance

Blue Back Blue Eye

Pseudomugil cyanodorsalis

False Glass Catfish

Kryptopterus macrocephalus

🐠Family Group
Blue Back Blue Eye
Rainbowfish
False Glass Catfish
Catfish
Temperament
Blue Back Blue Eye
Peaceful (2/10)
False Glass Catfish
Peaceful (2/10)
Temperature
✓ Compatible
Blue Back Blue Eye
22–30°C
False Glass Catfish
22–28°C
pH Range
✓ Compatible
Blue Back Blue Eye
7–8.5
False Glass Catfish
5–7
Hardness (dGH)
✗ No overlap
Blue Back Blue Eye
10–30
False Glass Catfish
1–8
Water Type
✗ No overlap
Blue Back Blue Eye
Brackish Required
False Glass Catfish
Freshwater Only
Flow Preference
✓ Compatible
Blue Back Blue Eye
Moderate
False Glass Catfish
Low
Min Tank Volume
Combined: 110 L
Blue Back Blue Eye
38 L
False Glass Catfish
110 L
Swimming Level
Shared: 1 zone
Blue Back Blue Eye
TopMiddle
False Glass Catfish
Middle
🏷️Behavior Tags
Blue Back Blue Eye
Nano / Bite-sized (Predation Risk)Jumper (Lid Required)Hyperactive / Fast SwimmerFry Predator
False Glass Catfish
Shy / Slow Moving (Easily Stressed)Fry PredatorShrimp Eater
Stocking calculator

Can your tank handle Blue Back Blue Eye and False Glass Catfish?

Compatibility is only part of the answer. Test both fish with your real tank size, current stock, and maintenance needs to see if you have enough space and a safe stocking level before you add them.

Blue Back Blue Eye
False Glass Catfish
Test both in my tank

Behaviour & Temperament

Both Blue Back Blue Eye and False Glass Catfish are peaceful species with an aggression score of 2/10. Their matching temperaments mean neither fish is likely to dominate the other in a shared aquarium.

Blue Back Blue Eye and False Glass Catfish both frequent the Middle (Open Water) region of the setup. This overlap can increase competition for space, so providing ample room and cover is important to keep both species comfortable.

Additional behavioural considerations to keep in mind: Hyperactive swimmers can stress shy, slow-moving species through constant motion. Shrimp eaters may also prey on very small nano fish.

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

Water Parameters

The safe temperature window for both species falls between 22°C and 28°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. Maintaining a stable value within this band is more important than hitting an exact number.

Hardness requirements are incompatible: Blue Back Blue Eye needs 10–30 dGH while False Glass Catfish requires 1–8 dGH.

Crucially, these species require different water types — one needs freshwater while the other requires brackish conditions. This is a hard barrier to keeping them together.

Tank Setup

To house Blue Back Blue Eye and False Glass Catfish together, plan for an aquarium of at least 110 litres with a minimum length of 90 cm. This recommendation combines the stricter species minimums with a community-load allowance so the pairing has realistic long-term space and filtration headroom.

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: Driftwood (Digestion/Hiding), Sand (Sifters), Plants - Densely covered, Plants - Floating, Leaf Litter/Blackwater. 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.

Why This Pairing Usually Fails in Practice

Blue Back Blue Eye and False Glass Catfish are the kind of pair that can look acceptable in a shop but become a maintenance problem at home. The main risk is not a single number in the chart; it is the way incompatible behavior, water needs, or pressure on space compounds over time once both fish are established in the same tank.

Suitable Tank Sizes

Standard aquarium sizes large enough for both Blue Back Blue Eye and False Glass Catfish.

Show 10 more tank sizes

Diet & Feeding

Feeding time deserves special attention with this pairing. False Glass Catfish is a known shrimp eater and may prey on small invertebrates or nano fish like Blue Back Blue Eye.

Frequently Asked Questions

Can Blue Back Blue Eye and False Glass Catfish live together?

No. This combination is not recommended. Key incompatibilities — such as different water type needs — make cohabitation unsafe.

What size tank do Blue Back Blue Eye and False Glass Catfish need?

A minimum of 110 litres (tank length at least 90 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 Blue Back Blue Eye and False Glass Catfish together?

Keep the aquarium between 22°C and 28°C. A target of around 25.0°C sits comfortably within both species' preferred ranges.

Are Blue Back Blue Eye or False Glass Catfish aggressive?

Blue Back Blue Eye is peaceful (2/10) and False Glass Catfish is peaceful (2/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Blue Back Blue Eye and False Glass Catfish need?

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

Editorial Review

Guidarium Editorial Desk

Reviewed against Guidarium care, stocking, and compatibility standards. Read the editorial policy.

Last reviewed
May 4, 2026
Last updated
May 4, 2026
Issues or corrections?
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