Compatibility Overview
Cherry Barb and Koi are generally not recommended to be housed together. The issues listed above — whether water parameter incompatibility, predation risk, or aggression — create conditions where one or both fish are likely to suffer harm or chronic stress.
| Factor | Cherry Barb | Koi | Verdict |
|---|---|---|---|
| Temperature | 73–81°F | 50–75°F | ⚠️ 73–75°F (narrow) |
| pH Range | 6.0–8.0 | 7.0–8.5 | ✅ 7.0–8.0 |
| Temperament | peaceful | peaceful | ✅ Compatible |
| Adult Size | 2 in | 24 in | ❌ 12× difference |
| Min. Group | 6+ | 2+ | See below |
| Min. Tank Size | 100 gallons (for both species) | — | |
✅ Compatibility Positives
❌ Incompatibility Reasons
Species Profiles
Cherry Barb — Puntius titteya
Unlike most barbs, cherry barbs are peaceful schooling fish safe with bettas and nano species. Males turn vivid red when in breeding condition.
Koi — Cyprinus rubrofuscus
Large pond fish that require hundreds of gallons and cool water. Will eat any fish small enough to fit in their mouth.
Frequently Asked Questions
Can Cherry Barb live with Koi?
Generally not recommended. Cherry Barb and Koi are generally not recommended to be housed together. The issues listed above — whether water parameter incompatibility, predation risk, or aggression — create conditions where one or both fish are likely to suffer harm or chronic stress.
What tank size do I need for Cherry Barb and Koi together?
A minimum of 100 gallons is recommended for keeping Cherry Barb and Koi together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Cherry Barb and Koi?
73–75°F (narrow)
Is a Cherry Barb aggressive toward a Koi?
Cherry Barb is peaceful and Koi is peaceful. Cherry Barb requires tropical water; Koi requires cold water. These environments are incompatible.