Gobioides broussonnetii (Dragon Goby / Violet Goby / Dragonfish Goby)
• Small fish safe: ✅ Yes
• Small invert safe: ✅ Mostly, but may eat very small shrimp
• Coral safe: ✅ Yes (not typically found in reef setups)
• Minimum tank size: 200L+ (preferably 250L+ for adults)
• Adult size: ~50 cm (20 inches)
• Diet: Omnivorous (algae, detritus, sinking pellets, frozen foods like bloodworms/brine shrimp)
• Be aware of: Requires brackish water for long-term health. Has poor eyesight and relies on taste and smell to find food. May be confused with freshwater gobies but thrives best in brackish setups.
Dragon Goby (Gobioides broussonnetii) – A Unique and Mysterious Bottom Dweller
The Dragon Goby, also known as the Violet Goby or Dragonfish Goby, is a long, eel-like fish with an almost prehistoric appearance. Its mysterious, dragon-like look and peaceful nature make it a fascinating addition to brackish aquariums, though it is sometimes mistakenly sold as a freshwater species. While it can tolerate freshwater for short periods, it requires brackish water for long-term health. Known for its sifting behavior and bottom-dwelling habits, it thrives best in tanks with soft sand, hiding spots, and dim lighting.
Appearance and Coloration
Dragon Gobies have a slender, elongated body, featuring:
• A violet to grayish-blue coloration, often appearing iridescent under light.
• A long, eel-like body, making them resemble mythical sea creatures.
• A wide mouth with tiny teeth, adapted for filtering food from the substrate.
• A large, sail-like dorsal fin, adding to their dragon-like appearance.
• Very small eyes, meaning they rely more on smell and touch than sight when feeding.
Their stunning metallic sheen and sinuous movements make them an eye-catching fish, despite their subtle colors.
Natural Habitat and Behaviour
Native to coastal estuaries, mangroves, and river mouths in Central and South America, Dragon Gobies inhabit brackish waters, where they:
• Sift through mud and sand, filtering small food particles and detritus.
• Hide in burrows, caves, or mangrove roots, retreating when threatened.
• Are highly peaceful, preferring to avoid conflict rather than engage in aggression.
• Grow quite large, requiring a spacious tank with plenty of floor space.
In captivity, they retain their burrowing and sand-sifting behaviors, making a deep sand bed essential for their well-being.
Tank Requirements and Water Parameters
Due to their large size and need for brackish water, Dragon Gobies require a well-maintained, stable setup.
• Minimum tank size: 200L+ (250L+ for fully grown adults)
• Temperature: 24–28°C (75–82°F)
• pH: 7.5–8.5
• Salinity: 1.005–1.010 (brackish water)
• Water movement: Moderate to strong
• Filtration: Good filtration with low nitrates to keep water clean.
A soft, sandy substrate is necessary, as Dragon Gobies sift through the substrate to find food. Hard gravel can damage their delicate mouths and gills.
Brackish Water Requirements
⚠ Despite being commonly sold as freshwater fish, Dragon Gobies need brackish water to thrive long-term.
• Gradually increase salinity if transitioning from freshwater.
• Use marine salt (not aquarium salt) to create brackish conditions.
• Maintain a specific gravity of 1.005–1.010 using a refractometer.
While they can survive in freshwater for months, they will eventually become sickly and prone to disease if kept outside of their natural brackish environment.
Diet and Feeding
Dragon Gobies are omnivorous filter feeders, requiring a mix of protein and plant-based foods.
Recommended foods include:
• Sinking algae wafers and spirulina-based pellets – A staple part of their diet.
• Frozen or live bloodworms and brine shrimp – Provides protein.
• Finely chopped seafood (shrimp, squid, or fish) – Occasional protein treats.
• Blanched vegetables (zucchini, spinach, peas) – Supports digestion.
Due to their poor eyesight, Dragon Gobies may take longer to find food. It’s best to place food near them or in sandy areas where they naturally sift for food. Target feeding can help ensure they get enough nutrients.
Compatibility and Tank Mates
Dragon Gobies are incredibly peaceful, making them ideal for community brackish setups.
✔ Mollies, Guppies, Knight Gobies, and Archerfish – Tolerate brackish water.
✔ Bumblebee Gobies and Scats – Other brackish tank mates that won’t outcompete them.
✔ Peaceful brackish invertebrates, such as Nerite Snails and Amano Shrimp.
Avoid housing with:
❌ Aggressive fish (e.g., Cichlids, Pufferfish, large Scats) that may harass them.
❌ Fast-feeding tank mates, as Dragon Gobies are slow eaters.
❌ Small shrimp species, which may be eaten.
If keeping multiple Dragon Gobies, ensure they have plenty of hiding spots and a large enough sand bed to establish separate territories.
Burrowing and Hiding Behavior
Dragon Gobies naturally dig burrows and hide under structures, so:
• Provide PVC pipes, caves, or rock formations for shelter.
• Use at least 2-3 inches of soft sand for natural sifting behavior.
• Avoid bright lighting – They prefer dim or shaded environments.
They are often most active at night or during low-light periods, making them an ideal fish for calm, well-planted tanks.
Health and Disease Considerations
Dragon Gobies are hardy, but they can suffer from:
• Marine Ich (Cryptocaryon irritans) – Often caused by poor water conditions or stress.
• Nutritional deficiencies – Can lead to weight loss or weakened immune systems.
• Gill infections – May occur if kept in poor substrate conditions.
To keep them healthy:
✔ Provide a varied diet, including algae and proteins.
✔ Maintain stable brackish water conditions.
✔ Keep sand clean to prevent bacterial buildup.
Lifespan and Long-Term Care
With proper care, Dragon Gobies can live up to 10 years, making them a long-term commitment for aquarists. Their unique appearance, peaceful nature, and helpful sand-sifting behavior make them a valuable addition to brackish tanks.
Why Choose a Dragon Goby?
✔ Unique dragon-like appearance – Unlike any other goby.
✔ Peaceful and community-friendly – Safe for most brackish fish.
✔ Sifts and cleans sand – Helps maintain substrate health.
✔ Grows up to 20 inches, making it a fascinating display fish.
✔ Highly interactive, especially when housed with other peaceful tank mates.
⚠ Important Considerations Before Buying a Dragon Goby:
🚫 Requires brackish water – Will not thrive in freshwater long-term.
🚫 Slow feeder – Needs targeted feeding to ensure proper nutrition.
🚫 Needs a soft sand bed – Avoid gravel to prevent mouth injuries.