Can Silver Flying Fox and Uaru Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 11, 2026
Not Recommended

Silver Flying Fox and Uaru are not recommended as tank mates due to no temperature overlap. Housing these species together is likely to result in stress, health problems, or direct harm to one or both fish.


At a Glance

Silver Flying Fox

Crossocheilus reticulatus

Uaru

Uaru amphiacanthoides

🐠Family Group
Silver Flying Fox
Cyprinids
Uaru
Cichlids - South American
Temperament
Silver Flying Fox
Mostly Peaceful (3/10)
Uaru
Mostly Peaceful (4/10)
Temperature
✗ No overlap
Silver Flying Fox
20–26°C
Uaru
27–30°C
pH Range
✓ Compatible
Silver Flying Fox
6–7.5
Uaru
5–7
Hardness (dGH)
✓ Compatible
Silver Flying Fox
2–15
Uaru
1–8
Water Type
✓ Compatible
Silver Flying Fox
Freshwater Only
Uaru
Freshwater Only
Flow Preference
✗ No overlap
Silver Flying Fox
High
Uaru
Low
Min Tank Volume
Combined: 400 L
Silver Flying Fox
200 L
Uaru
400 L
Swimming Level
Shared: 2 zones
Silver Flying Fox
BottomMiddle
Uaru
MiddleBottom
🏷️Behavior Tags
Silver Flying Fox
Hyperactive / Fast SwimmerJumper (Lid Required)Aggressive to same species/look-alikesAggressive Eater (Starves shy fish)
Uaru
Plant DestroyerShy / Slow Moving (Easily Stressed)Shrimp Eater
Stocking calculator

Can your tank handle Silver Flying Fox and Uaru?

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.

Silver Flying Fox
Uaru
Test both in my tank

Behaviour & Temperament

Silver Flying Fox is a generally mild-mannered species (3/10), while Uaru is generally mild-mannered (4/10). This modest difference means Uaru may occasionally assert dominance over Silver Flying Fox.

Silver Flying Fox and Uaru both frequent the Bottom (Substrate) and 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.

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: Silver Flying Fox is a known jumper, so a tight-fitting lid is essential.

Water Parameters

There is no temperature overlap between Silver Flying Fox (20–26°C) and Uaru (27–30°C). This fundamental mismatch makes long-term cohabitation impractical.

Both fish can tolerate a pH between 6 and 7. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 2–8 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Silver Flying Fox and Uaru together, plan for an aquarium of at least 400 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: Established Algae (Otocinclus), Smooth Gravel (Sensitive Barbels), Driftwood (Digestion/Hiding), Sand (Sifters). Meeting these requirements will help both species thrive.

Silver Flying Fox prefers High (River/Stream) flow while Uaru needs Low (Still Water) 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

Silver Flying Fox and Uaru 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 Silver Flying Fox and Uaru.

Diet & Feeding

Feeding time deserves special attention with this pairing. Silver Flying Fox is an aggressive eater that may prevent Uaru from getting enough food.

Because Silver Flying Fox is a fast, competitive feeder, consider using sinking pellets or feeding at opposite ends of the setup to ensure Uaru receives an adequate share.

Frequently Asked Questions

Can Silver Flying Fox and Uaru live together?

No. This combination is not recommended. Key incompatibilities — such as non-overlapping temperature ranges — make cohabitation unsafe.

What size tank do Silver Flying Fox and Uaru need?

A minimum of 400 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 Silver Flying Fox and Uaru together?

Unfortunately, there is no temperature range that satisfies both species. Silver Flying Fox requires 20–26°C, while Uaru needs 27–30°C.

Are Silver Flying Fox or Uaru aggressive?

Silver Flying Fox is generally mild-mannered (3/10) and Uaru is generally mild-mannered (4/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Silver Flying Fox and Uaru need?

Both species overlap in the 6–7 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.

Editorial Review

Guidarium Editorial Desk

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

Last reviewed
May 11, 2026
Last updated
May 11, 2026
Issues or corrections?
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