Compatibility Overview
Oscar and Pea Puffer 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 | Oscar | Pea Puffer | Verdict |
|---|---|---|---|
| Temperature | 74–81°F | 74–82°F | ✅ 74–81°F |
| pH Range | 6.0–8.0 | 7.0–8.0 | ✅ 7.0–8.0 |
| Temperament | aggressive | semi | ❌ Risk |
| Adult Size | 14 in | 1 in | ❌ 14× difference |
| Min. Group | 1+ | 1+ | See below |
| Min. Tank Size | 100 gallons (for both species) | — | |
✅ Compatibility Positives
❌ Incompatibility Reasons
Species Profiles
Oscar — Astronotus ocellatus
Intelligent but aggressive cichlids that will eat any fish small enough to fit in their mouth. Require large tanks (75+ gallons) and robust tank mates.
Pea Puffer — Carinotetraodon travancoricus
World's smallest pufferfish — intensely territorial and nippy despite tiny size. Will attack fins and eat shrimp and snails.
Frequently Asked Questions
Can Oscar live with Pea Puffer?
Generally not recommended. Oscar and Pea Puffer 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 Oscar and Pea Puffer together?
A minimum of 100 gallons is recommended for keeping Oscar and Pea Puffer together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Oscar and Pea Puffer?
74–81°F
Is a Oscar aggressive toward a Pea Puffer?
Oscar is aggressive and Pea Puffer is semi. Aggression risk is high; the aggressive species may dominate or injure the other.