Golden mugilogobius

Mugilogobius rexi

Also known as Rexi goby, Golden goby

FreshwaterFish

Golden mugilogobius (Mugilogobius rexi) — The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature: 75–82°F (24–28°C)
pH: 7.5–8.5
Adult size: 1.6 in (4 cm)
Minimum tank: 14 gal (54 L)
Temperament: Mostly peaceful
Social behavior: Social
Swim level: Bottom
Difficulty: Difficult
Breeding: No record
Rarity: Rare
Origin: Lake Poso, Sulawesi
Family: Oxudercidae

Overview

This is a small golden goby from an ancient Sulawesi lake, best kept as a biotope fish over sand and stone. It is mostly peaceful and social; keep a small group with cover from rocks and plants, giving mildly territorial fish room to settle. It stays near the bottom in deeper, calmer water and takes small meaty foods, so offer frozen and live items such as cyclops, brine, and finely chopped bloodworm alongside small sinking foods. It suits a hard-water community built around the lake's own fish, such as Sulawesi ricefish, rather than soft-water tankmates. Around 54 liters with sand, stone, and planted cover suits a group.

In the wild

In the wild it is restricted to Sulawesi in Indonesia, living along the margins of ancient Lake Poso over silty and sandy bottoms, near clumps of aquatic plants and freshwater mangrove roots. The lake water is warm, hard, and alkaline. Recreate that with a sand base, rock and root structure, gentle flow, and planted cover. Hold it at 24 to 28 C and clearly alkaline, roughly pH 7.5 to 8.5, with hard water.

Good to know

Mugilogobius rexi is a member of the family Oxudercidae, described by Larson in 2001. It is small, reaching about 4 centimeters, with males washed in a soft golden tone. It lives over silty substrate in deeper lake margins among plants, and there is no established record of it being bred in aquaria. It is one of the endemic fish of Lake Poso, part of Sulawesi's distinct ancient-lake faunas.

Did you know

Lake Poso is an ancient tectonic lake with animals found nowhere else, a fauna quite separate from the nearby Malili lakes. This little golden goby is one of Poso's own endemic residents.

Tank mates

Golden mugilogobius is a mostly peaceful, social species that keeps to the bottom. These picks match on water type, temperature, pH, size and temperament.