Can Australian Smelt and Festivum Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 4, 2026
Possible with Caution

Keeping Australian Smelt and Festivum together is possible but requires caution, though some care is needed. Provide a spacious tank of at least 150 litres with plenty of hiding spots to reduce stress. Monitor behaviour closely, especially during the first few weeks.


At a Glance

Australian Smelt

Retropinna semoni

Festivum

Mesonauta festivus

🐠Family Group
Australian Smelt
Other
Festivum
Cichlids - South American
Temperament
Australian Smelt
Peaceful (1/10)
Festivum
Mostly Peaceful (4/10)
Temperature
✓ Compatible
Australian Smelt
15–24°C
Festivum
24–28°C
pH Range
✓ Compatible
Australian Smelt
6.5–8
Festivum
5.5–7.2
Hardness (dGH)
✓ Compatible
Australian Smelt
5–20
Festivum
2–12
Water Type
✓ Compatible
Australian Smelt
Brackish Tolerant
Festivum
Freshwater Only
Flow Preference
✓ Compatible
Australian Smelt
Moderate
Festivum
Low
Min Tank Volume
Combined: 150 L
Australian Smelt
75 L
Festivum
150 L
Swimming Level
Shared: 2 zones
Australian Smelt
TopMiddle
Festivum
TopMiddle
🏷️Behavior Tags
Australian Smelt
Hyperactive / Fast SwimmerShy / Slow Moving (Easily Stressed)Fry PredatorJumper (Lid Required)
Festivum
Plant DestroyerJumper (Lid Required)Territorial (Defends specific area)
Stocking calculator

Can your tank handle Australian Smelt and Festivum?

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
Festivum
Test both in my tank

Behaviour & Temperament

Australian Smelt is a peaceful species (1/10), while Festivum is generally mild-mannered (4/10). This modest difference means Festivum may occasionally assert dominance over Australian Smelt.

Australian Smelt and Festivum 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.

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

To improve the chances of a peaceful coexistence in this community tank: Provide a significantly larger tank (at least 50% more volume than the minimum) to allow both Australian Smelt and Festivum to establish separate territories. Add plenty of line-of-sight breaks using driftwood, rocks, and dense planting to reduce territorial confrontations.

Water Parameters

The safe temperature window for both species falls between 24°C and 24°C. Aim for the midpoint of this range (around 24.0°C) for optimal comfort.

Both fish can tolerate a pH between 6.5 and 7.2. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 5–12 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Australian Smelt and Festivum together, plan for an aquarium of at least 150 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.

Because this pairing requires extra vigilance, include plenty of hiding spots — caves, driftwood, and dense plant clusters — so the less dominant fish can retreat when needed.

Specific environmental needs for this combination include: Plants - lighly covered, Smooth Gravel (Sensitive Barbels), Driftwood (Digestion/Hiding), Plants - Floating. Meeting these requirements will help both species thrive.

Note a potential conflict in setup requirements: Festivum is a plant destroyer, which conflicts with Australian Smelt's requirement for live plants. Compromise where possible or prioritise the more critical need.

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

Why This Pairing Needs Extra Planning in Practice

This pairing usually fails when the tank is treated like a standard mixed community and the caution flags are ignored. Australian Smelt and Festivum need extra room, more cover, and closer observation during the first few weeks so small aggression, feeding, or territory issues do not snowball into a long-term problem.

Suitable Tank Sizes

Standard aquarium sizes large enough for both Australian Smelt and Festivum.

Show 9 more tank sizes

Frequently Asked Questions

Can Australian Smelt and Festivum live together?

They can coexist, but the pairing requires careful monitoring. Provide ample space (at least 150 litres), plenty of hiding spots, and watch for signs of stress or aggression.

What size tank do Australian Smelt and Festivum need?

A minimum of 150 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 Australian Smelt and Festivum together?

Keep the aquarium between 24°C and 24°C. A target of around 24.0°C sits comfortably within both species' preferred ranges.

Are Australian Smelt or Festivum aggressive?

Australian Smelt is peaceful (1/10) and Festivum is generally mild-mannered (4/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Australian Smelt and Festivum need?

Both species overlap in the 6.5–7.2 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.

How do I manage Festivum's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Festivum space to claim a territory without encroaching on the other fish's area. Adding décor that divides the tank into distinct zones works especially well.

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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