Compatibility Overview
Clown Loach 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 | Clown Loach | Koi | Verdict |
|---|---|---|---|
| Temperature | 77–86°F | 50–75°F | ❌ No overlap |
| pH Range | 6.0–7.5 | 7.0–8.5 | ⚠️ 7.0–7.5 (narrow) |
| Temperament | peaceful | peaceful | ✅ Compatible |
| Adult Size | 12 in | 24 in | ⚠️ 2.0× difference |
| Min. Group | 5+ | 2+ | See below |
| Min. Tank Size | 100 gallons (for both species) | — | |
✅ Compatibility Positives
❌ Incompatibility Reasons
Species Profiles
Clown Loach — Chromobotia macracanthus
Striking striped loach that grows very large. Peaceful with fish but will eat shrimp, snails and tiny fish.
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 Clown Loach live with Koi?
Generally not recommended. Clown Loach 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 Clown Loach and Koi together?
A minimum of 100 gallons is recommended for keeping Clown Loach and Koi together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Clown Loach and Koi?
No overlap
Is a Clown Loach aggressive toward a Koi?
Clown Loach is peaceful and Koi is peaceful. Clown Loach requires tropical water; Koi requires cold water. These environments are incompatible.