Court Jester Goby

Also known as the Rainford Goby or Rainford’s Goby

The Court Jester Goby is a small, peaceful reef fish known for its striking colors and active personality. With bright green, orange, and blue stripes running along its body, it brings instant vibrancy to any aquarium. This species is gentle, calm, and spends its time grazing on algae and searching the sandbed for food. In the wild, they live in lagoons and shallow reefs of the Indo Pacific where they stay close to rockwork and seagrass beds.

Key Features

• Scientific Name: Koumansetta rainfordi
• Common Names: Court Jester Goby, Rainford Goby, Rainford’s Goby
• Adult Size: 2 to 2.5 inches (5 to 6.3 cm)
• Lifespan: 3 to 5 years with proper care
• Temperament: Peaceful and shy
• Reef Compatibility: Reef safe and beneficial because they help with algae control
• Minimum Tank Size: 20 gallons
• Experience Level: Intermediate due to feeding needs

Habitat and Tank Requirements

Natural Habitat: Court Jester Gobies are native to shallow reef flats, seagrass beds, and calm lagoon zones across the Indo Pacific. They spend most of their time near the sand and rock base searching for small organisms and film algae.

Tank Environment: Provide a sandbed for natural grazing and live rock with plenty of crevices. They prefer calm flow and peaceful tank mates. Works best singly or as a bonded pair in larger tanks.

 Water Parameters: 

• Temperature: 72 to 78°F (22 to 26°C)
• Salinity: 1.023 to 1.025
• pH: 8.1 to 8.4
•  Ammonia/Nitrite: 0 ppm
• Nitrate: Below 20 ppm
• Alkalinity: 8 to 12 dKH

Essential Equipment:

• Stable filtration with low to moderate water flow
• Good lighting to support natural microalgae growth
• Regular weekly or biweekly water changes

Diet and Feeding

Court Jester Gobies are omnivores with a strong preference for grazing. They naturally eat film algae, detritus, and tiny crustaceans found on sand and rocks.

Recommended Foods:

• Frozen mysis shrimp
• Frozen brine shrimp
• Copepods
• High quality omnivore pellets
• Algae based foods
• Live foods for picky eaters

Feeding Schedule: Feed 1 to 2 times daily. Provide a mature tank with natural microalgae or supplemental foods to support their grazing behavior.

Behavior and Compatibility

Temperament: Very peaceful, active, and gentle. They spend most of their day grazing along the sand and rock surfaces. They avoid conflict and do well in calm community tanks.

Tank Mates:

• Compatible with peaceful fish such as clown gobies, firefish, wrasses, blennies, cardinalfish, and other non aggressive species
• Use caution with larger or aggressive tank mates that may intimidate or outcompete them
• Best kept singly unless the tank is large enough for a pair

Breeding Potential

Court Jester Gobies may spawn in captivity if kept in a quiet, stable tank. They lay eggs inside crevices or small caves, and the male guards the eggs until they hatch. The fry are challenging to raise and require very small live foods such as rotifers and copepods.

Why Choose Us

At Dr Reefs, every Court Jester Goby goes through a complete quarantine process with careful observation for several weeks. Each fish is treated proactively for parasites and trained to accept a variety of foods so it adapts easily to home aquariums. Choosing Dr Reefs ensures you receive a healthy, conditioned, and well acclimated Court Jester Goby ready for a peaceful reef environment.