Compatibility Overview
Discus and Guppy 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 | Guppy | Verdict |
|---|---|---|---|
| Temperature | 82–88°F | 72–82°F | ⚠️ 82–82°F (narrow) |
| pH Range | 5.0–7.0 | 6.8–8.5 | ⚠️ 6.8–7.0 (narrow) |
| Temperament | semi | peaceful | ⚠️ Monitor |
| Adult Size | 8 in | 2.5 in | ⚠️ 3.2× difference |
| Min. Group | 5+ | 3+ | 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.
Guppy — Poecilia reticulata
Hardy and colourful livebearers. Males' long flowing tails make them targets for fin-nipping species. Very prolific breeders.
Frequently Asked Questions
Can Discus live with Guppy?
Generally not recommended. Discus and Guppy 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 Guppy together?
A minimum of 100 gallons is recommended for keeping Discus and Guppy together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Discus and Guppy?
82–82°F (narrow)
Is a Discus aggressive toward a Guppy?
Discus is semi and Guppy is peaceful. Minimal temperature overlap (82–82°F) — difficult to satisfy both species simultaneously.