Can True Julii Corydoras and Uaru Live Together?

Not Recommended

True Julii Corydoras 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

True Julii Corydoras

Corydoras julii

Uaru

Uaru amphiacanthoides

🐠Family Group
True Julii Corydoras
Catfish
Uaru
Cichlids - South American
Temperament
True Julii Corydoras
Peaceful (0/10)
Uaru
Mostly Peaceful (4/10)
Temperature
βœ— No overlap
True Julii Corydoras
23–26Β°C
Uaru
27–30Β°C
pH Range
βœ“ Compatible
True Julii Corydoras
6–7.5
Uaru
5–7
Hardness (dGH)
βœ“ Compatible
True Julii Corydoras
2–15
Uaru
1–8
Water Type
βœ“ Compatible
True Julii Corydoras
Freshwater Only
Uaru
Freshwater Only
Flow Preference
βœ“ Compatible
True Julii Corydoras
Moderate
Uaru
Low
Min Tank Volume
Combined: 400 L
True Julii Corydoras
60 L
Uaru
400 L
Swimming Level
Shared: 1 zone
True Julii Corydoras
Bottom
Uaru
MiddleBottom
🏷️Behavior Tags
True Julii Corydoras
Hyperactive / Fast Swimmer
Uaru
Plant DestroyerShy / Slow Moving (Easily Stressed)Shrimp Eater
Stocking calculator

Can your tank handle True Julii Corydoras 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.

True Julii Corydoras
Uaru
Test both in my tank

Behaviour & Temperament

True Julii Corydoras is a peaceful species (0/10), while Uaru is generally mild-mannered (4/10). This notable difference means Uaru may occasionally assert dominance over True Julii Corydoras.

True Julii Corydoras and Uaru 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.

Water Parameters

There is no temperature overlap between True Julii Corydoras (23–26Β°C) and Uaru (27–30Β°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 True Julii Corydoras 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: Sand (Sifters), Driftwood (Digestion/Hiding). Meeting these requirements will help both species thrive.

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

Suitable Tank Sizes

Standard aquarium sizes large enough for both True Julii Corydoras and Uaru.

Frequently Asked Questions

Can True Julii Corydoras and Uaru live together?

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

What size tank do True Julii Corydoras 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 True Julii Corydoras and Uaru together?

Unfortunately, there is no temperature range that satisfies both species. True Julii Corydoras requires 23–26Β°C, while Uaru needs 27–30Β°C.

Are True Julii Corydoras or Uaru aggressive?

True Julii Corydoras is peaceful (0/10) and Uaru is generally mild-mannered (4/10). The gap in aggression levels means the calmer fish may experience stress from the more assertive one.

What pH do True Julii Corydoras and Uaru need?

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


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