Can Frogmouth Catfish and Scat (Brackish) Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 6, 2026
Not Recommended

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


At a Glance

Frogmouth Catfish

Chaca chaca

Scat (Brackish)

Scatophagus argus

🐠Family Group
Frogmouth Catfish
Catfish
Scat (Brackish)
Oddballs
Temperament
Frogmouth Catfish
Aggressive (7/10)
Scat (Brackish)
Mostly Peaceful (4/10)
Temperature
✓ Compatible
Frogmouth Catfish
22–26°C
Scat (Brackish)
20–28°C
pH Range
✓ Compatible
Frogmouth Catfish
6–8
Scat (Brackish)
7.5–8.5
Hardness (dGH)
✓ Compatible
Frogmouth Catfish
4–15
Scat (Brackish)
12–30
Water Type
✗ No overlap
Frogmouth Catfish
Freshwater Only
Scat (Brackish)
Brackish Required
Flow Preference
✗ No overlap
Frogmouth Catfish
Low
Scat (Brackish)
High
Min Tank Volume
Combined: 450 L
Frogmouth Catfish
110 L
Scat (Brackish)
450 L
Swimming Level
Shared: 1 zone
Frogmouth Catfish
Bottom
Scat (Brackish)
MiddleBottom
🏷️Behavior Tags
Frogmouth Catfish
Piscivore (Eats small/nano fish)Shy / Slow Moving (Easily Stressed)NocturnalDigger (Disturbs Substrate)
Scat (Brackish)
Plant DestroyerHyperactive / Fast SwimmerAggressive Eater (Starves shy fish)Fin Nipper
Stocking calculator

Can your tank handle Frogmouth Catfish 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.

Frogmouth Catfish
Scat (Brackish)
Test both in my tank

Behaviour & Temperament

Frogmouth Catfish is a semi-aggressive species (7/10), while Scat (Brackish) is generally mild-mannered (4/10). This modest difference means Frogmouth Catfish may occasionally assert dominance over Scat (Brackish).

Frogmouth Catfish and Scat (Brackish) both frequent the Bottom (Substrate) 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. Aggressive eaters may outcompete shy fish for food, leading to malnutrition.

Worth noting: Frogmouth Catfish is nocturnal and will be most active after lights-out, naturally reducing daytime encounters.

Water Parameters

The safe temperature window for both species falls between 22°C and 26°C. Aim for the midpoint of this range (around 24.0°C) for optimal comfort.

Both fish can tolerate a pH between 7.5 and 8. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 12–15 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 Frogmouth Catfish 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: Sand (Sifters), Leaf Litter/Blackwater, Smooth Gravel (Sensitive Barbels), Established Algae (Otocinclus). Meeting these requirements will help both species thrive.

Frogmouth Catfish 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

Frogmouth Catfish 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 Frogmouth Catfish and Scat (Brackish).

Diet & Feeding

Feeding time deserves special attention with this pairing. Scat (Brackish) is an aggressive eater that may prevent Frogmouth Catfish from getting enough food.

Because Scat (Brackish) is a fast, competitive feeder, consider using sinking pellets or feeding at opposite ends of the setup to ensure Frogmouth Catfish receives an adequate share.

Frequently Asked Questions

Can Frogmouth Catfish 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 Frogmouth Catfish 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 Frogmouth Catfish and Scat (Brackish) together?

Keep the aquarium between 22°C and 26°C. A target of around 24.0°C sits comfortably within both species' preferred ranges.

Are Frogmouth Catfish or Scat (Brackish) aggressive?

Frogmouth Catfish is semi-aggressive (7/10) and Scat (Brackish) is generally mild-mannered (4/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Frogmouth Catfish and Scat (Brackish) need?

Both species overlap in the 7.5–8 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.

Will Scat (Brackish) nip Frogmouth Catfish's fins?

Scat (Brackish) is a known fin nipper. If Frogmouth Catfish 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.

Does Frogmouth Catfish being nocturnal affect compatibility?

Frogmouth Catfish is most active after lights-out, which naturally reduces daytime encounters with its tank mate. This can actually be beneficial, as both fish get undisturbed time to feed and explore. Just ensure food reaches Frogmouth Catfish during evening hours.

Editorial Review

Guidarium Editorial Desk

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

Last reviewed
May 6, 2026
Last updated
May 6, 2026
Issues or corrections?
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