Dragon Goby 101: Care, Diet, Tank Size, Tank Mates & More

The Dragon Goby is a long slender fish with an eel-like appearance. They have quite specific requirements to keep them healthy, but are still a popular option with both beginner and experienced aquarists. 

If you want to find out whether the Dragon Goby is the right species of fish for you, then keep reading. We will tell you everything you need to know about their tank requirements, diet, behaviour and more. 

Species Summary

Dragon Gobys are a species of Brackish fish also known as the Violet Goby. They originate in the bays and estuaries of the Atlantic shores- North, Central and South America.

Their natural habitat is muddy and swampy, and these bottom-feeders like to sift through sand and silt to look for food. Their pre-historic appearance makes them popular with people looking to add a more unusual fish to their aquarium. 

Care Guide

Tank Size

Dragon Gobys require a minimum of 25 gallons of water per fish, though 50 is recommended for optimum comfort and growth. You will also need to consider the shape of the tank. Longer is better, as it allows a better space for swimming.

The tank should be at least 4 feet long for one fish, 6ft long for two, or longer if you have more than two fish. There is a strong correlation between long, spacious tanks and long, healthy lifespans, so it is worth investing in a nice space for your fish to live in. 

Tank Mates

Dragon Gobys will get along with other brackish fish that have a peaceful temperament. It is best to pick medium sized fish like guppies, archers or monos, so the Dragon Gobys don’t mistake their tank mates for food. Avoid aggressive species as this timid fish is prone to being bullied. 

Same Species Tanks

Dragon Gobys can be housed in pairs or groups of four. If you plan on breeding them, it is best to have 2-3 females to one male. Ensure the tank is big enough for a group, as these placid fish can become territorial with their own species. 

Water Parameters

Dragon Gobys are brackish fish- they need too much salt to be classed as freshwater fish, but a lower salt content than what you would find in open sea water. They are very sensitive to chemical changes in the water such as rising levels of ammonia and nitrites so weekly 15% water changes are needed. 

The optimum temperature for the water is 72 degrees fahrenheit, abd should be no more than 82 degrees. The PH level of the water should sit within 6.5 and 8.5, and the water hardness between 10 and 20 KH. Use a hydrometer to monitor the salinity level of the water which should be between 1.006 – 1.008. 

To maintain these specific conditions and keep your fish healthy you will need to perform frequent water checks.

What To Put In Their Tank

You should aim to recreate a swampy environment like the estuaries of their natural habitat. Choose a dark substrate like black sand. Dragon Gobys will suck the sand into their mouth to sift for food, so gravel would be a dangerous choice of substrate. 

Some aquarists recommended mixing aragonite crystals in with the black sand to enrich the tank and help to maintain the water hardness and alkalinity. The dark sand prevents the crystals from catching the light and damaging the eyesight of the fish. 

Dragon Gobys are a shy species of fish so you need to provide them with plenty of hiding places in the tank. Add decorations like plants, rocks and caves- anything that offers shelter. Choose rocks that aren’t too sharp, as they could scratch themselves when nestling into their safe space. 

A wide variety of plant life is good for the fish and will keep them happy- try anubias, hairgrass and java fern. Dragon Goby are known for digging and disturbing the sand when looking for food, so the plants will need to be secured below the substrate level if possible. 

These fish are nocturnal and will spend most of the day hidden away. Medium lighting is enough to keep them happy. 

Common Diseases 

Most health issues experienced by this species are caused by poor diet, stress, or incorrect water conditions. They are vulnerable to diseases that affect many different species of fish found in domestic aquariums. 

Ich is a common parasite that causes white spots on the skin of the fish. Fin Rot is a bacterial infection that causes a white rim on the fin. This can be treated with antibiotics. Columnaris, also known as cottonmouth, is similar to fin rot. It causes decay on the gills and ulcers on the skin. This disease can also be treated with antibiotics. You will need to treat it quickly as it can be fatal.   

Food & Diet 

In the wild, Dragon Goby are omnivorous scavengers rather than hunters, and they will replicate this behaviour in a domestic environment. They have narrow throats so can only eat small pieces of food despite their large body size. 

You can feed them on a diet of sinking pellets, flakes and algae wafers. This dry diet should be supplemented with frozen or live food such as bloodworms, baby shrimp, and vegetables chopped into small pieces. 

Dragon Gobys should be fed once a day. To avoid over feeding, give them enough foodto keep them eating for no more than a few minutes. That should be enough, as they shouldn’t be eating for more than a few minutes every day.  


Dragon Gobys should live up to 10 years in a domestic aquarium. However, their lifespan is heavily influenced by their living conditions. As discussed earlier, a nice big tank with plenty of room to swim and grow will help them to live longer.

A nutrient rich diet will keep them healthy and help them to fight off illness. Avoiding stress will also help them to live longer, so be sure to choose the right tank mates. Maintaining the correct water parameters will also help your fish live a long and happy life. 


Dragon Gobys have long slender bodies and round heads. This, along with their dark colouring, means that they are often mistaken for eels. They have a short dorsal fin that runs along the length of their body, and a ventral fin behind each set of gills. The ventral fin is used for moving around and clinging onto rocks. 

These fish have sharp teeth which can make them look menacing, but in the wild they are only used for scraping algae off rocks. Dragon Gobys have very small eyes on the side of their head. Their vision is extremely poor to the point that they are almost blind. They use their mouths and fins to find their way around the tank. 

Dragon Gobys are sometimes brown/gray color, but in the right water conditions they become silvery blue which is why they are also called Violet Gobys. This blue color is splattered with patches of yellow- the more vibrant the coloring the healthier and happier the fish. They have a metallic appearance which is likened to dragon scales, hence the name Dragon Goby. 


In the wild, Dragon Gobys often grow larger than most other Goby species. They can reach lengths of up to 24 inches, but rarely exceed 15 inches in a home aquarium. Their size does depend on the size of the tank. In pet shops they are usually sold as juveniles at 4 to 5 inches long. 

Behaviour & Temperament 

These skittish bottom-dwellers are fairly timid and will spend a lot of time at the bottom of the tank. They can be territorial which may lead to displays of aggressive behaviour if they don’t have enough space in the tank. Dragon Goby are nocturnal and spend a lot of the daytime hiding, becoming more active at night. 


If you want to breed your Dragon Goby, you should start with a group of four made up of one male and 3 females, as the males will mate with multiple females in one day. 

Preparation for breeding is very important. Reduce their food gradually for a week beforehand, then provide a diet of protein-rich live food. Lower the salinity levels to 1.004 and the next day raise it to 1.023 to trigger the breeding cycle. 

The male will spawn with the females, and each female will lay several eggs. The females need to be removed from the tank, and the male will begin watching over the eggs. They will hatch within 2 days, which is when the male needs to be removed.  

Over the next month you will need to feed the smallfry simple algae, until they are big enough to eat baby shrimp. 

Gender Differences: Male vs Female

There are very few differences between males and females. The only reliable way to sex them is by looking at their genitalia. Males have pointed genitals but females have short yellow genitals. 

Fun Facts

They swallow a lot of sand when sifting for sand, and their large gills help them to filter and expel the sand.