Emerald Green Catfish

Once classified in its own genus Brochis, the Emerald Green Catfish is now recognized as Corydoras splendens, though hobbyists still use the Brochis name widely. It is notably larger and more robust than typical Corydoras, reaching up to 9 cm, with a higher dorsal fin and a more elongated body. The flanks shimmer with brilliant metallic green iridescence, giving the fish a jewel-like quality that is especially visible under bright lighting.

Native to the Amazon River basin in Peru, Ecuador, and Brazil, this species inhabits slow-moving to moderately flowing rivers, floodplains, and swampy areas with soft, fine substrate. Like all callichthyid catfish, it possesses bony scutes instead of scales for protection and uses intestinal respiration as a supplement to gill breathing, meaning it will periodically dart to the surface to gulp air — a completely normal behavior that should not alarm the keeper.

Emerald Green Catfish are highly social and must be kept in groups of at least six. In the aquarium, they are active, entertaining bottom-dwellers that constantly explore the substrate for food. They are compatible with virtually all peaceful community fish and will not harm plants, invertebrates, or other species. Their larger size compared to other corydoras makes them particularly visible and impressive in the aquarium.

Tank Setup A minimum 100-liter tank is recommended to accommodate a proper group of six or more. Use fine sand substrate to protect sensitive barbels. Provide hiding spots with driftwood, smooth rocks, and dense plant cover using Java Fern, Vallisneria, or Amazon Sword. Moderate water flow from a canister or hang-on-back filter is ideal.

Water Parameters Target pH 6.0–7.5, temperature 22–28°C. Soft to moderately hard water is preferred. Perform 25–30% weekly water changes. Avoid ammonia or nitrite spikes, as this species is sensitive to poor water quality despite its overall hardiness.

Feeding Offer sinking catfish pellets, algae wafers, and Repashy gel foods as staples. Supplement regularly with frozen bloodworms, brine shrimp, daphnia, and tubifex. They will also consume leftover food that sinks from upper-level feeders. Feed in the evening for best results.

Schooling Requirement Keep in groups of at least 6. Larger groups of 8–10 produce the most natural behavior and reduce individual stress. They can be kept alongside other Corydoras species.

Tankmates Ideal with peaceful mid-to-upper level community fish: tetras, rasboras, gouramis, and dwarf cichlids. Avoid large, aggressive fish that could bully or eat them.

Health Notes Inspect barbels regularly for erosion. Surface air-gulping is normal. Maintain excellent water quality to prevent fungal and bacterial infections. Quarantine new arrivals for 2–4 weeks.

Breeding Breeding is similar to other Corydoras species. Condition adults with live foods and trigger spawning with cooler water changes. Eggs are adhesive and deposited on plant leaves and glass. Remove adults post-spawning. Fry begin accepting baby brine shrimp after the yolk sac is absorbed. A separate breeding tank dramatically improves fry survival. A mature, well-cycled aquarium with established beneficial bacteria is strongly recommended before introducing this species. Never add to a new, uncycled tank. Ensure all group members are feeding by observing evening feeding sessions closely — shy individuals may be outcompeted by more confident groupmates in the initial weeks.