QUICK STATS

Care Level: Easy to Moderate
Diet: Carnivore
Temperament: Peaceful, May Be Territorial With Its Own Kind
Reef-Safe: Yes, With SPS Caution
Venomous/Toxic: Mild Toxic Mucus / Handle With Care
Approximate Purchase Size: 1-2"
Approximate Max Size: Around 2-2.75"
Recommended Tank Size: 10-20 Gallons or Larger

CITRON CLOWN GOBY

The Citron Clown Goby (Gobiodon citrinus) is a small, brightly colored reef fish known for its yellow to citron-colored body, blue facial markings, and perching behavior. Instead of constantly swimming through the aquarium, this goby prefers to sit on rockwork, coral branches, or favorite lookout spots like a tiny lemon-shaped security guard with absolutely no credentials.

Citron Clown Gobies are peaceful, hardy, and well-suited for smaller reef aquariums with calm tank mates. They are usually visible once settled and often develop a favorite perch where they spend much of the day watching the aquarium like they’re judging every maintenance decision.

This species is generally considered reef-safe, but it should be kept with caution in SPS-heavy systems. Citron Clown Gobies naturally associate with branching corals and may perch on or nip at small-polyp stony corals, especially Acropora. Most reef keepers tolerate this behavior in mixed reefs, but in delicate SPS systems, the tiny yellow goby can become a very cute inconvenience with fins.

Note: Image is a representation of what to expect. The fish you receive may vary slightly in size, color, markings, and overall appearance.

AQUARIUM REQUIREMENTS

AQUARIUM SIZE

A minimum tank size of 10 gallons or larger can work for a single Citron Clown Goby, though 20 gallons or larger is preferred for better stability and more room for tank mates.

Because this fish stays small and spends much of its time perched rather than swimming constantly, it can do well in nano reef aquariums when water quality is stable and tank mates are peaceful. For pairs or multiple clown gobies, a larger aquarium is recommended to reduce territorial behavior.

HABITAT RECOMMENDATIONS

Citron Clown Gobies do best in established aquariums with live rock, peaceful surroundings, and plenty of perching areas.

Aquascaping: Provide live rock, caves, ledges, branching coral skeletons, or other perching spots. These gobies enjoy sitting in elevated areas where they can watch the tank and pretend they are contributing to management.

Substrate: Sand, fine aragonite, crushed coral, or bare-bottom systems can work. This species does not rely heavily on the sandbed like many sand-sifting gobies.

Rockwork: Live rock is strongly recommended. It provides shelter, territory, biological filtration, and natural surfaces for perching.

Coral Structure: Branching corals or branching-style rockwork can help this fish feel secure, but use caution with delicate SPS colonies.

Tank Cover: A tight-fitting lid is recommended. Small gobies can jump, because apparently being two inches long does not prevent dramatic life choices.

WATER PARAMETERS

Citron Clown Gobies are generally hardy once established, but they still need clean, stable marine conditions. “Small and hardy” does not mean “immune to whatever chaos is happening in the nano tank this week.”

Temperature: 72-78°F
pH Level: 8.1-8.4
Salinity: 1.020-1.026 specific gravity
Ammonia, Nitrite, and Nitrate: Ammonia and nitrite should remain undetectable. Nitrate should be kept as low as reasonably possible, ideally below 20 ppm.
Water Flow: Low to moderate flow is ideal. Provide enough water movement to keep the aquarium oxygenated and move waste toward filtration, while still giving the goby calmer areas to perch comfortably.

DIET

Citron Clown Gobies are carnivores that should be offered a varied diet of small meaty foods. Because of their small size, they do best with appropriately sized foods that are easy to grab from the water column or nearby surfaces.

PRIMARY DIET

Frozen Food: Offer mysis shrimp, enriched brine shrimp, cyclops, finely chopped marine blends, and other small frozen foods. We at Summit City Coral prefer frozen foods such as LRS Reef Frenzy and PE Mysis.

Prepared Foods: High-quality small marine pellets, flakes, and prepared carnivore foods can help provide a balanced diet once the fish is eating reliably.

Live Foods: Copepods, amphipods, live brine shrimp, and other small live foods can help encourage feeding, especially in newly introduced or shy individuals.

Small Meaty Foods: Finely chopped seafood and small plankton-sized foods can help support natural feeding behavior. Avoid large chunky foods unless you enjoy watching a tiny goby contemplate physics.

FEEDING FREQUENCY

Feed small amounts 1-2 times per day, or 2-3 times per day for new, shy, or thinner individuals. In community tanks, make sure food reaches the Citron Clown Goby before faster fish inhale everything like tiny aquatic tax collectors.

COMPATIBILITY

Citron Clown Gobies are peaceful and work best with calm community fish. They should not be housed with aggressive tank mates that may harass, chase, or outcompete them.

COMMON TANK MATES

Fish: Clownfish, cardinalfish, firefish, peaceful gobies, blennies, small peaceful wrasses, chromis, and other calm community reef fish.

Avoid: Aggressive damsels, dottybacks that may harass them, large predatory fish, aggressive wrasses, triggers, groupers, lionfish, and any fish likely to bully or eat them.

Same Species: May fight with other Citron Clown Gobies or similar gobies in smaller tanks. A pair may work in a larger aquarium, but multiple individuals should be monitored.

Invertebrates: Safe with cleaner shrimp, hermit crabs, snails, urchins, and most common reef invertebrates.

Coral: Citron Clown Gobies are generally considered reef-safe with SPS caution. They usually ignore soft corals, LPS, zoanthids, mushrooms, clams, and anemones, but may perch on or irritate branching SPS corals, especially Acropora.

BEHAVIORAL NOTES

Temperament: Peaceful overall, though it may become territorial toward similar gobies or its own kind.

Perching Behavior: Frequently sits on rockwork, coral branches, or ledges rather than swimming constantly in open water.

SPS Caution: May perch on, irritate, or nip at small-polyp stony corals, especially branching Acropora. This is more important in SPS-dominant systems.

Reef Compatibility: Good for most mixed reef tanks, but best listed as reef-safe with caution due to possible SPS irritation.

Visibility: Often visible once settled, especially if kept with peaceful tank mates.

Toxic Mucus: Citron Clown Gobies can produce a protective mucus that may be mildly toxic or irritating. Avoid rough handling and use normal caution when transferring.

Feeding Risk: Small or shy individuals may be outcompeted by faster tank mates. Watch body condition and make sure they are eating well.

Jumping: A tight-fitting lid is recommended. Even tiny perch gobies can make catastrophic little launch decisions.

ACCLIMATION PROCESS

This acclimation method helps reduce stress by gradually introducing the fish to your aquarium’s temperature and water chemistry.

1. TURN OFF THE LIGHTS & ATO

Turn off aquarium lights to reduce stress. If you have an Auto Top Off system, switch it off before starting acclimation.

2. FLOAT THE BAG

Float the sealed bag in the aquarium for 15-20 minutes to allow the temperature in the bag to equalize with the tank.

3. OPEN BAG, ADD FISH TO CONTAINER

Carefully open the bag and transfer the fish and shipping water into a clean bucket or container.

4. ACCLIMATE USING TANK WATER

Add 1/4 cup of tank water to the container every 5 minutes for 40 minutes.

5. TRANSFER FISH TO AQUARIUM

Once acclimation is complete, gently transfer the fish into the aquarium using a net or specimen container. Discard the shipping water. Do not pour shipping water into your aquarium.

6. REFILL THE AQUARIUM WITH SALTWATER

You may need to replace the saltwater removed during acclimation with fresh mixed saltwater.