Can Festivum and Scat (Brackish) Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 4, 2026
Not Recommended

Festivum and Scat (Brackish) are not recommended as tank mates due to incompatible water types and conflicting pH requirements. Housing these species together is likely to result in stress, health problems, or direct harm to one or both fish.


At a Glance

Festivum

Mesonauta festivus

Scat (Brackish)

Scatophagus argus

🐠Family Group
Festivum
Cichlids - South American
Scat (Brackish)
Oddballs
Temperament
Festivum
Mostly Peaceful (4/10)
Scat (Brackish)
Mostly Peaceful (4/10)
Temperature
✓ Compatible
Festivum
24–28°C
Scat (Brackish)
20–28°C
pH Range
✗ No overlap
Festivum
5.5–7.2
Scat (Brackish)
7.5–8.5
Hardness (dGH)
✓ Compatible
Festivum
2–12
Scat (Brackish)
12–30
Water Type
✗ No overlap
Festivum
Freshwater Only
Scat (Brackish)
Brackish Required
Flow Preference
✗ No overlap
Festivum
Low
Scat (Brackish)
High
Min Tank Volume
Combined: 450 L
Festivum
150 L
Scat (Brackish)
450 L
Swimming Level
Shared: 1 zone
Festivum
TopMiddle
Scat (Brackish)
MiddleBottom
🏷️Behavior Tags
Festivum
Plant DestroyerJumper (Lid Required)Territorial (Defends specific area)
Scat (Brackish)
Plant DestroyerHyperactive / Fast SwimmerAggressive Eater (Starves shy fish)Fin Nipper
Stocking calculator

Can your tank handle Festivum and Scat (Brackish)?

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.

Festivum
Scat (Brackish)
Test both in my tank

Behaviour & Temperament

Both Festivum and Scat (Brackish) are generally mild-mannered species with an aggression score of 4/10. Their matching temperaments mean neither fish is likely to dominate the other in a shared aquarium.

Festivum and Scat (Brackish) 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.

Worth noting: Festivum 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 28°C. Aim for the midpoint of this range (around 26.0°C) for optimal comfort.

The pH requirements of Festivum (5.5–7.2) and Scat (Brackish) (7.5–8.5) do not overlap, making it impossible to satisfy both species simultaneously.

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

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 Festivum and Scat (Brackish) together, plan for an aquarium of at least 450 litres with a minimum length of 150 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), Plants - Floating, Sand (Sifters), Smooth Gravel (Sensitive Barbels), Established Algae (Otocinclus). Meeting these requirements will help both species thrive.

Festivum prefers Low (Still Water) flow while Scat (Brackish) needs High (River/Stream) flow. Consider positioning filter outlets and using baffles to create zones of different current intensity within the same tank.

Why This Pairing Usually Fails in Practice

Festivum and Scat (Brackish) 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 Festivum and Scat (Brackish).

Frequently Asked Questions

Can Festivum and Scat (Brackish) live together?

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

What size tank do Festivum and Scat (Brackish) need?

A minimum of 450 litres (tank length at least 150 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 Festivum and Scat (Brackish) together?

Keep the aquarium between 24°C and 28°C. A target of around 26.0°C sits comfortably within both species' preferred ranges.

Are Festivum or Scat (Brackish) aggressive?

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

What pH do Festivum and Scat (Brackish) need?

Their pH requirements do not overlap. Festivum prefers 5.5–7.2, while Scat (Brackish) needs 7.5–8.5. This makes them incompatible in the same water chemistry.

Will Scat (Brackish) nip Festivum's fins?

Scat (Brackish) is a known fin nipper. If Festivum has long or flowing fins, there is a real risk of fin damage. Keeping Scat (Brackish) in a larger group can help redirect nipping behaviour toward conspecifics.

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
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