Can Assassin Snail and Green Neon Tetra Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 6, 2026
Not Recommended

Assassin Snail and Green Neon Tetra are not recommended as tank mates due to 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

Assassin Snail

Anentome helena

Green Neon Tetra

Paracheirodon simulans

🐠Family Group
Assassin Snail
Invertebrates
Green Neon Tetra
Characins
Temperament
Assassin Snail
Peaceful (2/10)
Green Neon Tetra
Peaceful (0/10)
Temperature
✓ Compatible
Assassin Snail
22–28°C
Green Neon Tetra
24–29°C
pH Range
✗ No overlap
Assassin Snail
7–8
Green Neon Tetra
4.5–6.5
Hardness (dGH)
✓ Compatible
Assassin Snail
8–15
Green Neon Tetra
1–8
Water Type
✓ Compatible
Assassin Snail
Freshwater Only
Green Neon Tetra
Freshwater Only
Flow Preference
✓ Compatible
Assassin Snail
Low
Green Neon Tetra
Low
Min Tank Volume
Combined: 38 L
Assassin Snail
10 L
Green Neon Tetra
38 L
Swimming Level
✓ Different zones
Assassin Snail
Bottom
Green Neon Tetra
Middle
🏷️Behavior Tags
Assassin Snail
Nano / Bite-sized (Predation Risk)Snail EaterDigger (Disturbs Substrate)
Green Neon Tetra
Nano / Bite-sized (Predation Risk)Shy / Slow Moving (Easily Stressed)
Stocking calculator

Can your tank handle Assassin Snail and Green Neon Tetra?

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
Green Neon Tetra
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Behaviour & Temperament

Assassin Snail is a peaceful species (2/10), while Green Neon Tetra is peaceful (0/10). This modest difference means Assassin Snail may occasionally assert dominance over Green Neon Tetra.

In terms of spatial distribution, Assassin Snail prefers the Bottom (Substrate) zone, whereas Green Neon Tetra occupies the Middle (Open Water) zone. Because they use different levels of the water column, territorial disputes are less likely and the tank will appear more balanced.

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 Assassin Snail (7–8) and Green Neon Tetra (4.5–6.5) do not overlap, making it impossible to satisfy both species simultaneously.

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

Tank Setup

To house Assassin Snail and Green Neon Tetra together, plan for an aquarium of at least 38 litres with a minimum length of 45 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, Plants - Densely covered, Plants - Floating. 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.

Why This Pairing Usually Fails in Practice

Assassin Snail and Green Neon Tetra 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 Assassin Snail and Green Neon Tetra.

Show 22 more tank sizes

Frequently Asked Questions

Can Assassin Snail and Green Neon Tetra 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 Green Neon Tetra need?

A minimum of 38 litres (tank length at least 45 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 Green Neon Tetra 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 Assassin Snail or Green Neon Tetra aggressive?

Assassin Snail is peaceful (2/10) and Green Neon Tetra is peaceful (0/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Assassin Snail and Green Neon Tetra need?

Their pH requirements do not overlap. Assassin Snail prefers 7–8, while Green Neon Tetra needs 4.5–6.5. This makes them incompatible in the same water chemistry.

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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