Otocinclus and Royal Gramma Compatibility Overview
Otocinclus and Royal Gramma are generally not recommended to be housed together. One of these is a marine species and the other is not; they cannot share one aquarium. Their pH ranges do not meet: Otocinclus wants 6.0โ7.5 and Royal Gramma wants 8.1โ8.4. Review the behavior and water details before deciding whether to attempt the pairing.
| Factor | Otocinclus | Royal Gramma | Verdict |
|---|---|---|---|
| Temperature | 72โ82ยฐF | 72โ82ยฐF | โ 72โ82ยฐF |
| pH Range | 6.0โ7.5 | 8.1โ8.4 | โ No overlap |
| Temperament | peaceful | semi | โ ๏ธ Monitor |
| Adult Size | 1.5 in | 3.0 in | โ ๏ธ 2.0ร difference |
| Min. Group | 4+ | 1+ | See below |
| Min. Tank Size | 20 gallons (for both species) | โ | |
Compatibility Positives
Incompatibility Reasons
Species Profiles
Otocinclus โ Otocinclus spp.
Tiny algae-eating catfish that are peaceful with all species. Need established algae growth and biofilm; sensitive to ammonia.
โ Full Otocinclus care guide
Royal Gramma โ Gramma loreto
The Royal Gramma, known for its vibrant blue coloration, is a popular saltwater fish among beginners and experienced aquarists alike. It requires a well-maintained tank with plenty of swimming space and a moderate current. With a peaceful temperament and a relatively easy care routine, the Royal Gramma can be a great addition to a community tank.
Frequently Asked Questions
Can Otocinclus live with Royal Gramma?
Generally not recommended. Otocinclus and Royal Gramma are generally not recommended to be housed together. One of these is a marine species and the other is not; they cannot share one aquarium. Their pH ranges do not meet: Otocinclus wants 6.0โ7.5 and Royal Gramma wants 8.1โ8.4. Review the behavior and water details before deciding whether to attempt the pairing.
What tank size do I need for Otocinclus and Royal Gramma together?
A minimum of 20 gallons is recommended for keeping Otocinclus and Royal Gramma together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Otocinclus and Royal Gramma?
72โ82ยฐF โ inside Otocinclus's 72โ82ยฐF and Royal Gramma's 72โ82ยฐF.
Is a Otocinclus aggressive toward a Royal Gramma?
Otocinclus is peaceful and Royal Gramma is semi. No major aggression issues are expected between these species.
Related Compatibility Guides
Tank Size for Otocinclus and Royal Gramma
Use the scenario that matches the actual group sizes and temperament you plan to keep.
| Scenario | Tank | When it applies |
|---|---|---|
| Minimum viable | 30 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 | 75 gal | Best when keeping larger schools or reducing territorial pressure. |