๐Ÿ  Fish Compatibility Guide

Can Harlequin Rasbora and Red Eye Tetra Live Together?

Updated September 23, 2026 ยท FishCare AI Editorial Team

โœ… Compatible โ€” Compatibility Score: 86/100
86/100 โ€” Compatible

Harlequin Rasbora and Red Eye Tetra Compatibility Overview

Harlequin Rasbora and Red Eye Tetra can generally share an aquarium with appropriate planning. Both species prefer overlapping temperature and pH ranges. Harlequin Rasbora is peaceful and Red Eye Tetra is semi, so give them room and cover rather than assuming they will ignore each other. A minimum 20-gallon tank is recommended to provide adequate territory and water volume for both species.

Compatibility factors for Harlequin Rasbora and Red Eye Tetra
FactorHarlequin RasboraRed Eye TetraVerdict
Temperature72โ€“81ยฐF72โ€“79ยฐFโœ… 72โ€“79ยฐF
pH Range5.5โ€“7.56.0โ€“8.0โœ… 6.0โ€“7.5
Temperamentpeacefulsemiโš ๏ธ Monitor
Adult Size1.75 in2.8 inโœ… Similar
Min. Group8+6+See below
Min. Tank Size20 gallons (for both species)โ€”

Compatibility Positives

A stable shared temperature range is available.
Their pH requirements overlap.
Temperament risk is relatively low when normal group sizes are maintained.

Caution Points

No major compatibility issues identified for this pair.

Species Profiles

Harlequin Rasbora โ€” Trigonostigma heteromorpha

Harlequin Rasbora and Red Eye Tetra compatibility โ€” Harlequin Rasbora

Active mid-level schooling fish with a distinctive black triangular patch. One of the best all-around community tank fish.

โ†’ Full Harlequin Rasbora care guide

Red Eye Tetra โ€” Moenkhausia sanctaefilomenae

Harlequin Rasbora and Red Eye Tetra compatibility โ€” Red Eye Tetra

The Red Eye Tetra is a popular freshwater fish known for its vibrant red eyes and sleek, silver body. They are generally peaceful and can be kept in a community tank with other non-aggressive species. Their moderate activity level makes them suitable for a variety of aquarium setups. With proper care, they can live up to 5 years.

โ†’ Full Red Eye Tetra care guide

Frequently Asked Questions

Can Harlequin Rasbora live with Red Eye Tetra?

Yes, in a well-planned setup. Harlequin Rasbora and Red Eye Tetra can generally share an aquarium with appropriate planning. Both species prefer overlapping temperature and pH ranges. Harlequin Rasbora is peaceful and Red Eye Tetra is semi, so give them room and cover rather than assuming they will ignore each other. A minimum 20-gallon tank is recommended to provide adequate territory and water volume for both species.

What tank size do I need for Harlequin Rasbora and Red Eye Tetra together?

A minimum of 20 gallons is recommended for keeping Harlequin Rasbora and Red Eye Tetra together. A larger tank improves water stability and reduces territorial conflict.

What temperature suits both Harlequin Rasbora and Red Eye Tetra?

72โ€“79ยฐF โ€” inside Harlequin Rasbora's 72โ€“81ยฐF and Red Eye Tetra's 72โ€“79ยฐF.

Is a Harlequin Rasbora aggressive toward a Red Eye Tetra?

Harlequin Rasbora is peaceful and Red Eye Tetra is semi. No major aggression issues are expected between these species.

Related Compatibility Guides

Tank Size for Harlequin Rasbora and Red Eye Tetra

Use the scenario that matches the actual group sizes and temperament you plan to keep.

ScenarioTankWhen it applies
Minimum viable27 galOnly for the recommended minimum groups, mature filtration, and close monitoring.
Recommended community40 galAdds territory, swimming room, and a safer buffer for behavior.
Low-conflict setup75 galBest when keeping larger schools or reducing territorial pressure.