Compatibility Overview
Firefish Goby and Harlequin Rasbora 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 | Firefish Goby | Harlequin Rasbora | Verdict |
|---|---|---|---|
| Temperature | 72–81°F | 72–81°F | ✅ 72–81°F |
| pH Range | 8.1–8.4 | 5.5–7.5 | ❌ No overlap |
| Temperament | semi | peaceful | ⚠️ Monitor |
| Adult Size | 1.2 in | 1.75 in | ✅ Similar |
| Min. Group | 1+ | 8+ | See below |
| Min. Tank Size | 40 gallons (for both species) | — | |
✅ Compatibility Positives
❌ Incompatibility Reasons
Species Profiles
Firefish Goby — Aquarium species
The Firefish Goby is a popular choice for saltwater aquariums due to its vibrant colors and peaceful nature. These goby fish thrive in well-maintained tanks with plenty of live rock for them to explore. They are best kept in pairs or small groups and can be a great addition to a community tank with compatible species. It's important to provide them with a sp
→ Full Firefish Goby care guide
Harlequin Rasbora — Trigonostigma heteromorpha
Active mid-level schooling fish with a distinctive black triangular patch. One of the best all-around community tank fish.
Frequently Asked Questions
Can Firefish Goby live with Harlequin Rasbora?
Generally not recommended. Firefish Goby and Harlequin Rasbora 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 Firefish Goby and Harlequin Rasbora together?
A minimum of 40 gallons is recommended for keeping Firefish Goby and Harlequin Rasbora together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Firefish Goby and Harlequin Rasbora?
72–81°F
Is a Firefish Goby aggressive toward a Harlequin Rasbora?
Firefish Goby is semi and Harlequin Rasbora is peaceful. These animals require different water types and cannot share one aquarium.
Related Compatibility Guides
Compatibility score breakdown
The overall score is weighted across water chemistry, behavior, adult size, swimming zone, and social needs. A score is a planning aid—not a guarantee for individual fish.
| Factor | Score |
|---|---|
| Temperature | 100/100 |
| Ph | 0/100 |
| Temperament | 75/100 |
| Adult Size | 100/100 |
| Swim Zone | 92/100 |
| Social Needs | 92/100 |
Tank size scenarios
Use the scenario that matches the actual group sizes and temperament you plan to keep.
| Scenario | Tank | When it applies |
|---|---|---|
| Minimum viable | 40 gal | Only for the recommended minimum groups, mature filtration, and close monitoring. |
| Recommended community | 55 gal | Adds territory, swimming room, and a safer buffer for behavior. |
| Low-conflict setup | 90 gal | Best when keeping larger schools or reducing territorial pressure. |