Can Finger Fish and Flying Fox Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 6, 2026
Not Recommended

Finger Fish and Flying Fox 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

Finger Fish

Monodactylus argenteus

Flying Fox

Epalzeorhynchos kalopterus

🐠Family Group
Finger Fish
Oddballs
Flying Fox
Cyprinids
Temperament
Finger Fish
Semi-Aggressive (5/10)
Flying Fox
Aggressive (7/10)
Temperature
✓ Compatible
Finger Fish
24–28°C
Flying Fox
24–28°C
pH Range
✓ Compatible
Finger Fish
7.5–8.5
Flying Fox
6–7.5
Hardness (dGH)
✓ Compatible
Finger Fish
12–30
Flying Fox
2–12
Water Type
✗ No overlap
Finger Fish
Brackish Required
Flying Fox
Freshwater Only
Flow Preference
✓ Compatible
Finger Fish
Moderate
Flying Fox
Moderate
Min Tank Volume
Combined: 470 L
Finger Fish
470 L
Flying Fox
110 L
Swimming Level
✓ Different zones
Finger Fish
Middle
Flying Fox
Bottom
🏷️Behavior Tags
Finger Fish
Hyperactive / Fast SwimmerFin NipperPlant DestroyerAggressive to same species/look-alikes
Flying Fox
Territorial (Defends specific area)Aggressive to same species/look-alikesHyperactive / Fast SwimmerJumper (Lid Required)
Stocking calculator

Can your tank handle Finger Fish and Flying Fox?

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.

Finger Fish
Flying Fox
Test both in my tank

Behaviour & Temperament

Finger Fish is a moderately assertive species (5/10), while Flying Fox is semi-aggressive (7/10). This modest difference means Flying Fox may occasionally assert dominance over Finger Fish.

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

Worth noting: Flying Fox 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.

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

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 Finger Fish and Flying Fox together, plan for an aquarium of at least 470 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: Smooth Gravel (Sensitive Barbels), Driftwood (Digestion/Hiding), Plants - Densely covered. Meeting these requirements will help both species thrive.

Note a potential conflict in setup requirements: Finger Fish is a plant destroyer, which conflicts with Flying Fox'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 Usually Fails in Practice

Finger Fish and Flying Fox 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 Finger Fish and Flying Fox.

Frequently Asked Questions

Can Finger Fish and Flying Fox live together?

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

What size tank do Finger Fish and Flying Fox need?

A minimum of 470 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 Finger Fish and Flying Fox 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 Finger Fish or Flying Fox aggressive?

Finger Fish is moderately assertive (5/10) and Flying Fox is semi-aggressive (7/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Finger Fish and Flying Fox need?

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

Will Finger Fish nip Flying Fox's fins?

Finger Fish is a known fin nipper. If Flying Fox has long or flowing fins, there is a real risk of fin damage. Keeping Finger Fish in a larger group can help redirect nipping behaviour toward conspecifics.

How do I manage Flying Fox's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Flying Fox 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 6, 2026
Last updated
May 6, 2026
Issues or corrections?
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