Red Tail Goby
Red Tail Goby (Sicyopterus lagocephalus) is a specialized algae-grazing hillstream goby closely related to Stiphodon. Males develop vivid red to orange-red coloration in the tail region contrasting with a darker body — a striking two-tone effect. One of the larger Sicyopterus species. Like all Sicydiinae gobies, it is an amphidromous species with a life cycle that requires marine conditions for larval development — captive breeding is not possible. Wild-caught specimens require established algae growth and pristine, well-oxygenated water.
Feeding & Care Tip: Live algae and biofilm on rocks and glass are the primary food source — established algae growth is essential before adding this fish. Supplement with Hikari Mini Algae Wafers placed on rocks and blanched vegetables. Hikari Frozen or Freeze-Dried Baby Brine Shrimp very sparingly.
⚠ Algae Requirement: Like Otocinclus catfish, Stiphodon gobies are specialized algae and biofilm grazers that cannot survive without established live algae growing on rocks, glass, and hardscape. A tank without significant algae and biofilm growth will not sustain these fish regardless of supplemental feeding. Allow algae to establish thoroughly before adding Stiphodon. Hikari Mini Algae Wafers placed directly on rocks supplement but do not replace live algae growth. Blanched zucchini or spinach on rocks provides additional plant matter.
Stiphodon gobies inhabit clear, fast-flowing, well-oxygenated hillstreams with rocky substrate covered in algae and biofilm. The aquarium should replicate these conditions: strong filtration, good water movement, rocky substrate and hardscape with established algae growth, and pristine water quality. These fish are sensitive to elevated nitrates and should never be added to immature aquariums. Males are territorial with each other but peaceful with other species.
Note on Breeding: Stiphodon gobies have an amphidromous life cycle — adults live and spawn in freshwater streams, but the newly hatched larvae drift downstream to the ocean where they spend the first weeks developing in marine conditions before migrating back upstream into fresh water. This remarkable journey sometimes involves climbing waterfalls using their modified pelvic fins as suction cups. Captive breeding is not possible due to this marine larval stage.
A specialist fish for the hillstream goby enthusiast. All Sicydiinae gobies share the same fundamental requirements: pristine water, strong oxygenation, established algae growth, and a tight-fitting lid. Within these parameters they are rewarding and often spectacular fish.
Care & Ideal Parameters
| Difficulty | Moderate |
| Temperament | Peaceful — males territorial with each other |
| Typical Adult Size | 5.0 inches (12.5 cm) |
| Min. Group Size | 1 male to 2+ females |
| Ideal Temp | 72–82°F (22–28°C) |
| Ideal pH | 7.0–8.0 |
| Ideal GH | 4–15 dGH |
| Ideal KH | 2–8 dKH |
| Staple Food | Live algae and biofilm (on rocks and glass); Hikari Mini Algae Wafers placed on rocks |
| Treat / Supplement | Blanched zucchini or spinach placed on rocks; Hikari Frozen or Freeze-Dried Baby Brine Shrimp very sparingly |
| Origin | Widespread across the Indo-Pacific — Philippines, Indonesia, and Pacific islands |
| Notes | Larger Sicyopterus — plan for adult size. Vivid red-orange tail in males. Amphidromous. Tight lid essential. Stiphodon gobies are expert climbers — a tight-fitting lid is essential. |