Compatibility Overview
Pea Puffer and Rainbow Shark 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 | Pea Puffer | Rainbow Shark | Verdict |
|---|---|---|---|
| Temperature | 74–82°F | 72–79°F | ✅ 74–79°F |
| pH Range | 7.0–8.0 | 6.5–7.5 | ⚠️ 7.0–7.5 (narrow) |
| Temperament | semi | semi | ⚠️ Monitor |
| Adult Size | 1 in | 6 in | ❌ 6× difference |
| Min. Group | 1+ | 1+ | See below |
| Min. Tank Size | 55 gallons (for both species) | — | |
✅ Compatibility Positives
❌ Incompatibility Reasons
Species Profiles
Pea Puffer — Carinotetraodon travancoricus
World's smallest pufferfish — intensely territorial and nippy despite tiny size. Will attack fins and eat shrimp and snails.
Rainbow Shark — Epalzeorhynchos frenatum
Active bottom dweller that becomes territorial at maturity. One per tank; avoid other shark-like or bottom-dwelling species.
Frequently Asked Questions
Can Pea Puffer live with Rainbow Shark?
Generally not recommended. Pea Puffer and Rainbow Shark 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 Pea Puffer and Rainbow Shark together?
A minimum of 55 gallons is recommended for keeping Pea Puffer and Rainbow Shark together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Pea Puffer and Rainbow Shark?
74–79°F
Is a Pea Puffer aggressive toward a Rainbow Shark?
Pea Puffer is semi and Rainbow Shark is semi. Narrow temperature overlap (74–79°F) — keeping the tank at exactly 75–78°F is needed for both species.