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Dragon Goby for Sale: Brackish Water Care Guide, Diet, and Tank Requirements
Dragon Goby for Sale: Brackish Water Care Guide, Diet, and Tank Requirements
Most fish stores label it wrong. Most hobbyists buy it wrong. And most Dragon Gobies end up in the wrong tank for exactly those two reasons.
The Dragon Goby is one of the most visually striking and genuinely prehistoric-looking fish available in the aquarium hobby. Its long, eel-like body, shimmering violet to silver-blue skin, and rows of tiny teeth give it an appearance that looks like it swam out of a fantasy novel. People see it in a tank and immediately want one. The problem is that almost everything sold alongside it tells you the wrong story about what kind of fish it actually is.
Here is the truth: the Dragon Goby is not a standard saltwater fish. It is not a reef fish. It is a brackish water specialist that lives in estuaries, mangroves, and river mouths where fresh and salt water mix. Put it in a full marine reef tank and it will slowly decline no matter how good your water is. Give it the right brackish setup and it will thrive, grow to an impressive 12 to 15 inches, and live for 6 to 10 years as one of the most conversation-starting fish in your home.
This guide gives you everything you need to do it right.
What Is the Dragon Goby?
The Dragon Goby goes by the scientific name Gobioides broussonnetii. It is also known as the Violet Goby and Dragon Fish Goby. It is native to the Atlantic coastal zone from South Carolina all the way south to Brazil, living in brackish estuaries, mudflats, mangrove roots, and river mouths where salinity fluctuates naturally.
The body is long and laterally compressed, very similar in shape to an eel or a small moray. Adults in captivity typically reach 12 to 15 inches in length. Wild specimens can grow even larger, sometimes reaching 20 to 24 inches, though this is rare in home aquariums. The coloration shifts depending on conditions and lighting, ranging from grey-brown to a striking violet or silvery blue that looks almost metallic under aquarium lights. That color shift is part of what gives the fish such visual drama.
The Dragon Goby available at Dr. Reef’s Quarantined Fish is priced at $99.99 and ships as a small to medium juvenile. Every specimen goes through a full quarantine protocol before sale, which matters significantly for this species given its specialized care requirements.
Dragon Goby at a Glance
- Scientific Name: Gobioides broussonnetii
- Common Names: Dragon Goby, Violet Goby, Dragon Fish Goby
- Adult Size: 12 to 15 inches in captivity; up to 24 inches in the wild
- Lifespan: 6 to 10 years with proper care
- Temperament: Peaceful and non-aggressive; may be territorial toward its own kind
- Reef Compatible: No. Requires brackish water. Not suitable for reef tanks
- Minimum Tank Size: 55 gallons, long footprint preferred
- Water Type: Brackish, 1.005 to 1.010 specific gravity
- Care Level: Intermediate to Advanced
- Diet: Carnivore and detritus scavenger
- Price at Dr. Reef’s: $99.99
The Single Most Important Thing to Understand
A Dragon Goby kept at full marine salinity (1.023 to 1.025) will show signs of stress within days. A Dragon Goby kept in pure freshwater will also decline. The sweet spot of 1.005 to 1.010 is where this fish is genuinely comfortable and where it will display its full color, full appetite, and full personality.
Setting up a brackish tank is not complicated. You use the same marine salt mix you would for a saltwater tank, just in a much smaller ratio per gallon of RODI water. A quality refractometer is essential for hitting and holding the target range accurately. Consistency matters more than any exact number within the target range. Swinging from 1.005 to 1.015 and back is far more harmful than holding steady at either end.
Tank Requirements for the Dragon Goby
Tank Size and Shape
A minimum of 55 gallons is required, and the shape matters. Dragon Gobies are bottom-dwelling fish with long bodies that need horizontal space to move. A long, wide tank is always better than a tall narrow one for this species. A standard 55-gallon tank at 48 inches long is a solid starting point. A 75-gallon or larger gives the fish even more room to express natural behavior and is strongly recommended for any specimen expected to reach full adult size.
Substrate
This is as critical for the Dragon Goby as it is for the Yellowhead Jawfish. Dragon Gobies are benthic sifters. They move along the bottom with their mouths, sifting through soft substrate in search of food and organic material. They also partially bury themselves when resting or hiding.
Use fine sand or soft silt-like substrate. Pure aragonite sand works well in a brackish setup. Avoid gravel, coarse crushed coral, or any jagged substrate. The Dragon Goby has a soft, scaleless-looking skin around its mouth and jaw area. Rough substrate causes abrasions and mouth injuries that become infection sites. This is one of the most common and preventable causes of health decline in captive specimens.
Aim for a substrate depth of at least 2 to 3 inches across the tank floor, with deeper areas near caves and hiding spots.
Lighting and Hiding Spots
Dragon Gobies are nocturnal to crepuscular, meaning they are most active in low light conditions, at dusk, and at night. Bright, intense lighting stresses them and pushes them into hiding permanently. Use moderate to low lighting, and provide multiple hiding spots using PVC pipe sections, clay caves, driftwood, or smooth rock formations. The fish should always have a place to feel secure during the day.
A tank with good hiding options produces a Dragon Goby that ventures out more often, not less. Counterintuitively, giving this fish places to hide makes it more visible and more active on average.
Water Flow
Use gentle to moderate flow. Dragon Gobies live in estuaries where water movement is calm and tidal rather than turbulent. Strong directional flow from powerheads aimed at the bottom disturbs sifting behavior and stresses the fish. Return nozzles should be positioned to create gentle circulation rather than strong current.
Good biological filtration is essential. Dragon Gobies are messy feeders that sift through substrate and leave organic waste. A canister filter or sump with generous biological media is recommended. Plan for weekly water changes of 15 to 20 percent to keep nitrates under control and water quality stable.
Water Parameters for the Dragon Goby
- Temperature: 72 to 78 degrees Fahrenheit
- Salinity: 1.005 to 1.010 specific gravity (brackish)
- pH: 7.0 to 8.2 (neutral to slightly alkaline)
- Ammonia: 0 ppm
- Nitrite: 0 ppm
- Nitrates: Keep below 20 ppm
Test water parameters weekly when first setting up a brackish tank. Once established, bi-weekly testing is sufficient as long as your maintenance routine is consistent.
Diet and Feeding the Dragon Goby
Here is where most Dragon Goby keepers run into problems. This fish has very poor eyesight. It cannot track moving food through the water column the way a normal fish does. It relies primarily on its sense of smell and its sifting behavior to find food near or in the substrate. Drop food into open water above a Dragon Goby and it may never find it.
In the wild, Dragon Gobies are omnivorous scavengers. They sift through muddy substrate, consuming algae, organic detritus, tiny invertebrates, and microorganisms. In captivity, they need a combination of meaty foods and plant-based nutrition.
The best foods for Dragon Gobies include frozen bloodworms, frozen or live brine shrimp, frozen mysis shrimp, tubifex worms, small pieces of shrimp or krill, sinking carnivore pellets, spirulina flakes, and algae wafers. The mix of meaty and plant-based foods mirrors their wild omnivorous diet and supports long-term health.
The critical feeding technique is placement. Use a target feeder, feeding stick, or long pipette to place food directly on the substrate near the fish’s head or in front of its burrow area. Sinking pellets and wafers that fall to the bottom naturally are excellent because the Dragon Goby will discover them during its normal sifting routine.
Feed small amounts daily or every other day. Because they cannot compete for food in open water, Dragon Gobies in community tanks need food placed directly for them. If they are expected to compete with faster, sharp-sighted tank mates, they will lose every time and slowly waste away from malnutrition.
A pre-quarantined specimen from Dr. Reef’s has already been conditioned to accept prepared foods before shipping. This head start on feeding acclimation dramatically improves outcomes for a species that is notoriously slow to adapt to new food sources after the stress of shipping.
Temperament and Tank Mates
The Dragon Goby is peaceful toward almost all other species. It has no interest in chasing, nipping, or competing with other fish. It spends the vast majority of its time on the substrate, sifting and slowly moving through its territory.
The one exception is toward other Dragon Gobies. Two males in a tank without enough space will conflict over bottom territory. A single specimen is the safest approach in any tank under 75 gallons. In larger systems, a single male kept with one or two females, or a small group in a very large tank with divided territories, can work.
Suitable brackish tank mates include figure eight puffers kept with caution since they can nip fins, archerfish, mollies and other brackish-adapted livebearers, mono fish, scats, and other peaceful brackish gobies. Avoid any fast, aggressive feeders that will compete for the substrate food the Dragon Goby depends on.
This fish is absolutely not compatible with a marine reef tank. It cannot tolerate full marine salinity, and it would not survive with the high-flow, bright-light environment that reef tanks require.
Questions and Answers About the Dragon Goby
Q: Is the Dragon Goby a saltwater fish or freshwater fish?
A: Neither, strictly speaking. It is a brackish water fish that requires a specific gravity of 1.005 to 1.010. It lives naturally in estuaries where fresh and salt water mix. It cannot thrive in a full marine reef tank or in pure freshwater.
Q: How big does the Dragon Goby get?
A: In captivity, most Dragon Gobies grow to 12 to 15 inches. Wild specimens can reach 20 to 24 inches. Tank size plays a significant role in growth rate and final adult size.
Q: What do Dragon Gobies eat?
A: They are omnivorous scavengers. The best diet includes frozen bloodworms, brine shrimp, mysis shrimp, sinking carnivore pellets, spirulina flakes, and algae wafers. Because of their poor eyesight, food must be placed directly on the substrate near their location.
Q: Can Dragon Gobies be kept with other fish?
A: Yes, with careful selection. They are peaceful toward most other brackish species. Avoid aggressive fin nippers and fish that will out-compete them for bottom food. They may be territorial toward other Dragon Gobies in smaller tanks.
Q: Why is my Dragon Goby hiding all the time?
A: This is normal behavior, especially during the day. Dragon Gobies are nocturnal and naturally hide during daylight hours. Bright lighting and lack of hiding spots worsen this. Dim the tank, add hiding places, and the fish will become more visible during feeding times and in the evening.
Q: What substrate is best for a Dragon Goby?
A: Fine sand or soft silt. Never use gravel or coarse crushed coral. Rough substrate causes mouth and body abrasions that lead to infection. Fine sand allows the fish to sift naturally and rest comfortably without injury.
Q: How long does a Dragon Goby live?
A: With proper brackish water, correct substrate, and good feeding management, Dragon Gobies live 6 to 10 years in captivity. Many losses happen in the first year due to wrong salinity or poor feeding technique rather than the fish’s natural limitations.
Q: What is the price of the Dragon Goby at Dr. Reef’s?
A: The Dragon Goby is $99.99 at drreefsquarantinedfish.com. An extended guarantee is available: 7 days for an additional $20.00 or 14 days for an additional $30.00.
Why Buy Your Dragon Goby From Dr. Reef’s Quarantined Fish?
The Dragon Goby is one of the species where the source matters most. An unquarantined Dragon Goby that arrives carrying parasites and internal infections will decline in a brackish setup just as fast as in any other system. Because this fish is already a moderate to advanced care challenge, starting with a compromised specimen almost guarantees failure.
Every Dragon Goby at Dr. Reef’s goes through a full medical quarantine protocol before it ships. That means the fish has been observed, treated if necessary, and conditioned to eat prepared foods before it arrives at your door. A pre-quarantined Dragon Goby removes the biggest risk factor in the first 30 days of ownership.
Dr. Reef’s ships every order overnight via UPS, Tuesday through Thursday, for Wednesday through Friday delivery. Free shipping applies on orders over $500. Payments are accepted via PayPal, Stripe, and Venmo. Extended guarantee options are available at checkout for extra peace of mind. A 24/7 email support team is there for any questions about your order, your setup, or your fish.