Can Australian Smelt and Delicate Blue-Eye Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 4, 2026
Not Recommended

Australian Smelt and Delicate Blue-Eye are not recommended as tank mates due to no temperature overlap. Housing these species together is likely to result in stress, health problems, or direct harm to one or both fish.


At a Glance

Australian Smelt

Retropinna semoni

Delicate Blue-Eye

Pseudomugil tenellus

🐠Family Group
Australian Smelt
Other
Delicate Blue-Eye
Rainbowfish
Temperament
Australian Smelt
Peaceful (1/10)
Delicate Blue-Eye
Peaceful (1/10)
Temperature
✗ No overlap
Australian Smelt
15–24°C
Delicate Blue-Eye
25–32°C
pH Range
✓ Compatible
Australian Smelt
6.5–8
Delicate Blue-Eye
5–7.5
Hardness (dGH)
✓ Compatible
Australian Smelt
5–20
Delicate Blue-Eye
5–15
Water Type
✓ Compatible
Australian Smelt
Brackish Tolerant
Delicate Blue-Eye
Brackish Tolerant
Flow Preference
✓ Compatible
Australian Smelt
Moderate
Delicate Blue-Eye
Moderate
Min Tank Volume
Combined: 75 L
Australian Smelt
75 L
Delicate Blue-Eye
60 L
Swimming Level
Shared: 2 zones
Australian Smelt
TopMiddle
Delicate Blue-Eye
TopMiddle
🏷️Behavior Tags
Australian Smelt
Hyperactive / Fast SwimmerShy / Slow Moving (Easily Stressed)Fry PredatorJumper (Lid Required)
Delicate Blue-Eye
Nano / Bite-sized (Predation Risk)Hyperactive / Fast SwimmerJumper (Lid Required)Fry Predator
Stocking calculator

Can your tank handle Australian Smelt and Delicate Blue-Eye?

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.

Australian Smelt
Delicate Blue-Eye
Test both in my tank

Behaviour & Temperament

Both Australian Smelt and Delicate Blue-Eye are peaceful species with an aggression score of 1/10. Their matching temperaments mean neither fish is likely to dominate the other in a shared aquarium.

Australian Smelt and Delicate Blue-Eye both frequent the Top (Surface) and 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.

Worth noting: Australian Smelt is a known jumper, so a tight-fitting lid is essential.

Water Parameters

There is no temperature overlap between Australian Smelt (15–24°C) and Delicate Blue-Eye (25–32°C). This fundamental mismatch makes long-term cohabitation impractical.

Both fish can tolerate a pH between 6.5 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.

Tank Setup

To house Australian Smelt and Delicate Blue-Eye together, plan for an aquarium of at least 75 litres with a minimum length of 60 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: Plants - lighly covered, Smooth Gravel (Sensitive Barbels), Plants - Densely covered, Plants - Floating. 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

Australian Smelt and Delicate Blue-Eye 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 Australian Smelt and Delicate Blue-Eye.

Show 17 more tank sizes

Frequently Asked Questions

Can Australian Smelt and Delicate Blue-Eye live together?

No. This combination is not recommended. Key incompatibilities — such as non-overlapping temperature ranges — make cohabitation unsafe.

What size tank do Australian Smelt and Delicate Blue-Eye need?

A minimum of 75 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 Australian Smelt and Delicate Blue-Eye together?

Unfortunately, there is no temperature range that satisfies both species. Australian Smelt requires 15–24°C, while Delicate Blue-Eye needs 25–32°C.

Are Australian Smelt or Delicate Blue-Eye aggressive?

Australian Smelt is peaceful (1/10) and Delicate Blue-Eye is peaceful (1/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Australian Smelt and Delicate Blue-Eye need?

Both species overlap in the 6.5–7.5 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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