Knight Goby - Stigmatogobius Sadanundio | Live Freshwater Fish

Natural habitat

The Knight Goby (Stigmatogobius sadanundio) hails from tropical freshwater regions of Colombia and surrounding South American waterways. In the home aquarium, it thrives as a compact bottom-dweller that naturally patrols the substrate and tank decor. A sandy substrate mirrors its natural environment, supporting its digging tendencies and minimizing display disruption while it goes about its confident, methodical patrolling.

Adult size

Approximately 4 inches at maturity, offering a manageable footprint for mid-sized tanks without sacrificing dynamic behavior.

Temperament

Semi-aggressive by nature, the Knight Goby actively defends its chosen territory around the substrate and decor. When kept with peaceful, similarly sized tank mates and provided ample hiding spots, it coexists well in community setups. Avoid pairing with significantly larger or more aggressive species that could disrupt its territorial balance.

Tank size

Minimum 30 gallons. A larger tank gives this active bottom-dweller room to roam, establish a territory, and reduce any potential pecking order issues with other inhabitants.

Diet

Omnivore that readily accepts a varied menu: flakes, frozen brine shrimp, daphnia, and algae wafers. Offer multiple small feedings to ensure all tank members receive nutrition, and supplement with occasional live or frozen foods to stimulate natural foraging behavior.

Compatibility

Best in community or species tanks with peaceful, similarly sized fish. Provide ample hiding spots and a sandy substrate to prevent excessive sand stirring. Large groups or very active oddball species can unsettle this goby; match with habitat-friendly companions and maintain a calm, well-structured environment.

Care level

Intermediate. Stable water conditions, regular maintenance, and balanced feeding are key to long-term health and activity. A consistently clean tank with gentle water flow supports its natural behavior and reduces stress.

Water parameters

pH 7.0–7.8; temperature 72–78°F (22–26°C).

Breeding notes

Breeding information for the Knight Goby is not widely documented in hobbyist settings. If breeding is pursued, expect specialized conditions and careful observation, as successful captive reproduction is less commonly reported.

Store quarantine statement

Quarantine notice: All Knight Goby are quarantined and observed for a minimum of 7 days before entering our main system. This careful screening reduces the risk of introducing pests or diseases into your established tank. We still recommend quarantine after purchase to ensure the healthiest, most stable addition to your aquarium.

Important note about care and appearance: Some pictures shown are of full-grown adults. Juvenile Knight Gobies may look different in color and pattern as they mature, so do not judge size or markings based solely on images.