Stigmatogobius sadanundio 4 - (Stigmatogobius sadanundio) — 4-7cm

Overview

The goby fish enthusiast will find Stigmatogobius sadanundio, commonly known as the butterfly goby, a striking bottom-dwelling species with bold personality, best suited to well-structured tanks with meaty diets and carefully chosen tankmates. Native to South Asia and Southeast Asia, including India, Sri Lanka, the Andaman Islands, and Indonesia, this distinctive goby inhabits estuaries and tidal river zones, thriving in both fresh and slightly brackish waters. Available for sale UK aquarists should note that this species requires moderate-level care with semi-aggressive temperament and specialized habitat requirements. At 4-7cm, these specimens are approaching adult size and ready for an appropriately designed aquarium.

Appearance and Colouration

Stigmatogobius sadanundio displays a robust, elongated body with a broad head and prominent eyes positioned high on the skull. Colouration features a base of olive-brown to grey with dark blotches, mottling, or banding creating an attractive camouflage pattern. The fins are well-developed, with the pelvic fins fused into a ventral sucker disc used for clinging to rocks and substrate. Males tend to develop more intense colouration and larger size than females. At 4-7cm, specimens display the characteristic robust build and patterning, reaching full adult size of around 7cm. The overall appearance is compact, muscular, and adapted for bottom-dwelling life.

Natural Habitat

Native to estuaries and tidal zones of rivers across South Asia to Southeast Asia, Stigmatogobius sadanundio inhabits mostly fresh waters with occasional brackish incursions. These environments feature sandy or muddy substrates, submerged wood, rocks, and moderate to low flow. Water conditions vary with tidal influences, creating fluctuating salinity and turbidity. In the wild, butterfly gobies are territorial bottom dwellers that burrow, establish territories around favoured hiding spots, and hunt small invertebrates and organic matter. Recreating these conditions with sandy substrate, hiding places, and stable water chemistry supports natural behaviour.

Aquarium Setup

Provide a minimum of 100 litres with ample floor space for territorial establishment. Use a soft, fine substrate such as sand to allow natural burrowing behaviour. Furnish the aquarium with caves, driftwood, smooth rocks, and PVC tubes to create hiding places and visual barriers. Maintain strong filtration with gentle to moderate water flow. Subdued lighting or floating plants help reduce stress and encourage natural behaviour. Install a secure, tight-fitting lid to prevent escapes. Perform regular partial water changes to maintain excellent water quality. Although often sold for freshwater aquariums, this species may benefit from slightly brackish conditions (specific gravity 1.002-1.005).

Diet and Feeding

Stigmatogobius sadanundio is a carnivore that requires a meaty, varied diet. Offer small live and frozen foods such as bloodworms, brine shrimp, daphnia, mysis, chopped earthworms, and quality sinking carnivore pellets. This species may accept prepared foods once established, though live and frozen options are strongly preferred. Feed once or twice daily in the evening, when the goby is most active. Remove uneaten food after a few hours to maintain water quality. A varied, protein-rich diet promotes vibrant colouration, healthy growth, and breeding condition. Ensure all tankmates can access food, as gobies can be competitive feeders.

Behaviour and Temperament

Stigmatogobius sadanundio is semi-aggressive, territorial, and primarily bottom-dwelling. Males establish territories around caves or favoured hiding spots and may display aggression towards other bottom dwellers, especially conspecifics. This species is most active during dawn, dusk, and night, often resting in caves or burrows during the day. They are curious and will investigate all areas of the aquarium floor. During spawning periods, males may display intensified colouration and territorial behaviour. Despite territorial tendencies, they are generally peaceful towards fish that occupy upper or midwater levels and are not small enough to be eaten.

Suitable Tank Mates

Compatible with robust peaceful fish that occupy upper or midwater levels and are not small enough to be eaten, such as larger barbs, rainbowfish, robust tetras, and peaceful livebearers. Other non-competitive bottom dwellers may coexist only in very large, well-structured tanks with clear territories. Species that tolerate similar freshwater to slightly brackish conditions are ideal. Avoid very small fish or fry that may be eaten, slow long-finned fish such as bettas or angelfish, highly aggressive or highly territorial bottom fish, and tiny shrimp or small ornamental invertebrates. Careful tankmate selection is essential.

Breeding

Breeding is possible in captivity but uncommon. Pairs typically spawn in a cave or sheltered crevice, with the male guarding the eggs until they hatch. Provide excellent water quality, stable parameters, and abundant hiding places to encourage spawning. Condition breeding pairs with high-quality live and frozen foods. Fry require very small live foods such as infusoria or newly hatched brine shrimp and excellent water quality. Successful breeding demands careful attention and stable, pristine conditions. Most aquarists keep Stigmatogobius sadanundio for display rather than reproduction.

Special Considerations

Provide a secure lid to prevent escapes, as gobies are capable climbers. Use sandy or fine substrate to allow natural burrowing behaviour. Furnish the aquarium with caves, driftwood, and subdued lighting with strong filtration but gentle flow. Although often sold as freshwater, this species may benefit from slightly brackish water (specific gravity 1.002-1.005), which replicates natural tidal conditions and supports optimal health. Monitor water quality closely and perform regular partial water changes. This species is best suited to aquarists with experience managing territorial bottom dwellers and specialized habitat requirements.

Why Buy from Tropical Fish Co

Tropical Fish Co is a leading UK supplier of healthy, vibrant goby species including Stigmatogobius sadanundio butterfly gobies. Each fish is carefully selected for bold markings, active behaviour, and robust health. Our livestock is quarantined and health-checked before dispatch, ensuring you receive only the finest specimens. We provide expert care advice, detailed species information, and ongoing support to help you succeed with specialist fish. With fast, secure delivery across the UK and a commitment to sustainable, responsible fishkeeping practices, Tropical Fish Co is your trusted partner for premium tropical fish and aquatic livestock.