Compatibility Overview
Discus and Goldfish 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 | Discus | Goldfish | Verdict |
|---|---|---|---|
| Temperature | 82–88°F | 50–74°F | ❌ No overlap |
| pH Range | 5.0–7.0 | 6.5–8.0 | ⚠️ 6.5–7.0 (narrow) |
| Temperament | semi | peaceful | ⚠️ Monitor |
| Adult Size | 8 in | 12 in | ✅ Similar |
| Min. Group | 5+ | 1+ | See below |
| Min. Tank Size | 100 gallons (for both species) | — | |
✅ Compatibility Positives
❌ Incompatibility Reasons
Species Profiles
Discus — Symphysodon spp.
The 'king of the aquarium' — beautiful but demanding. Requires very warm, soft, acidic water that excludes most community fish.
Goldfish — Carassius auratus
Classic pond and aquarium fish that prefer cool water. Heavy waste producers that require robust filtration. Will eat small fish and shrimp.
Frequently Asked Questions
Can Discus live with Goldfish?
Generally not recommended. Discus and Goldfish 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 Discus and Goldfish together?
A minimum of 100 gallons is recommended for keeping Discus and Goldfish together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Discus and Goldfish?
No overlap
Is a Discus aggressive toward a Goldfish?
Discus is semi and Goldfish is peaceful. Discus requires tropical water; Goldfish requires cold water. These environments are incompatible.