Can Assassin Snail and Freshwater Shark (Wallago) Live Together?

Not Recommended

Assassin Snail and Freshwater Shark (Wallago) are not recommended as tank mates due to piscivorous fish will prey on nano-sized tank mates.. Housing these species together is likely to result in stress, health problems, or direct harm to one or both fish.


At a Glance

Assassin Snail

Anentome helena

Freshwater Shark (Wallago)

Wallago attu

🐠Family Group
Assassin Snail
Invertebrates
Freshwater Shark (Wallago)
Catfish
Temperament
Assassin Snail
Peaceful (2/10)
Freshwater Shark (Wallago)
Highly Aggressive (10/10)
Temperature
✓ Compatible
Assassin Snail
22–28°C
Freshwater Shark (Wallago)
19–29°C
pH Range
✓ Compatible
Assassin Snail
7–8
Freshwater Shark (Wallago)
6–7.6
Hardness (dGH)
✓ Compatible
Assassin Snail
8–15
Freshwater Shark (Wallago)
1–20
Water Type
✓ Compatible
Assassin Snail
Freshwater Only
Freshwater Shark (Wallago)
Freshwater Only
Flow Preference
✓ Compatible
Assassin Snail
Low
Freshwater Shark (Wallago)
Moderate
Min Tank Volume
Combined: 5500 L
Assassin Snail
10 L
Freshwater Shark (Wallago)
5500 L
Swimming Level
Shared: 1 zone
Assassin Snail
Bottom
Freshwater Shark (Wallago)
MiddleBottom
🏷️Behavior Tags
Assassin Snail
Nano / Bite-sized (Predation Risk)Snail EaterDigger (Disturbs Substrate)
Freshwater Shark (Wallago)
Piscivore (Eats small/nano fish)Generally AggressiveAggressive to same species/look-alikesJumper (Lid Required)Hyperactive / Fast Swimmer
Stocking calculator

Can your tank handle Assassin Snail and Freshwater Shark (Wallago)?

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.

Assassin Snail
Freshwater Shark (Wallago)
Test both in my tank

Behaviour & Temperament

Assassin Snail is a peaceful species (2/10), while Freshwater Shark (Wallago) is highly aggressive (10/10). This notable difference means Freshwater Shark (Wallago) may occasionally assert dominance over Assassin Snail.

Large aggression gap (8 points) between Assassin Snail and Freshwater Shark (Wallago) increases stress risk for the more peaceful fish.

Assassin Snail and Freshwater Shark (Wallago) 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.

There is a critical concern: the Nano / Bite-sized (Predation Risk) behaviour of one fish directly conflicts with the Piscivore (Eats small/nano fish) trait of the other — piscivorous fish will prey on nano-sized tank mates..

Worth noting: Freshwater Shark (Wallago) 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 7.6. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 8–15 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Assassin Snail and Freshwater Shark (Wallago) together, plan for an aquarium of at least 5500 litres with a minimum length of 300 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), Smooth Gravel (Sensitive Barbels). Meeting these requirements will help both species thrive.

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

Frequently Asked Questions

Can Assassin Snail and Freshwater Shark (Wallago) live together?

No. This combination is not recommended. Key incompatibilities — such as critical behavioural conflicts — make cohabitation unsafe.

What size tank do Assassin Snail and Freshwater Shark (Wallago) need?

A minimum of 5500 litres (tank length at least 300 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 Assassin Snail and Freshwater Shark (Wallago) 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 Assassin Snail or Freshwater Shark (Wallago) aggressive?

Assassin Snail is peaceful (2/10) and Freshwater Shark (Wallago) is highly aggressive (10/10). The gap in aggression levels means the calmer fish may experience stress from the more assertive one.

What pH do Assassin Snail and Freshwater Shark (Wallago) need?

Both species overlap in the 7–7.6 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.


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