Common Names: Dojo Loach
Scientific Name: Misgurnus anguillicaudatus
Minimum Tank Size: 55 Gallons
Care Level: Moderate
Max Size: 6 Inches
Temperature: 65-80 F
Tank Level: Bottom
Colors: Red, Yellow
Dojo Loach Species Overview
Dojo loaches have excellent personalities matching their unique shape. They’re popular for the energetic flair they bring to an aquarium and their docile nature with other fish.
It doesn’t take a rocket scientist to care for the dojo loach, which is why they make an excellent tropical fish species for beginners.
But even though these fish are hardy, it’s still essential to set them up with the right tank conditions so that they live long and happy lives.
It’s easy to mistake a dojo loach for a freshwater eel. Their fins are barely noticeable, and they have long snake-shaped bodies.
The dojo loach has a round body except for the area near its tail, where it flattens.
These bottom-dwelling fish use their downward-facing pectoral fins to navigate the substrate. They spend most of their time there and have a dorsal fin towards their backend to further help with navigation.
Five large barbells frame the dojo loach’s mouth. It also has two small barbells that hang down from its lower lip.
If you look closely, you’ll see a series of miniature barbells below the dojo loach’s eyes.
These barbells serve purposes other than creating an aesthetically pleasing look in a fish tank. They help dojo loaches search for food and bury themselves in the substrate.
Although all dojo loaches share similar physical traits, they vary greatly in their color patterns. Some of the most common colors they come in include:
- Light brown
- Olive green
Admittedly, the gold color isn’t natural. Instead, commercial breeders worked to draw out this trait, allowing fish keepers to enjoy a more colorful version of this delightful species.
Regardless of their color, they may or may not have a lighter underbelly.
Also, depending on the dojo loach’s genetic makeup, they sometimes have dark brown spots. These spots help dojo loaches to stay off their predators’ radar.
Dojo loaches originate from the freshwaters of Southeast Asia, although there are over 200 varieties within this species. You can now find them living in more northern countries, such as China, Japan, and Russia.
These fish prefer living in shallow water such as rivers, swamps, and streams. Dojo loaches enjoy mud and leaf substrate, which is soft enough for them to burrow.
Dojo loaches have a toughness about them, unlike most other tropical fish. Because they gravitate towards shallow water in the wild, dry weather can reduce or eliminate their water source.
But dojo loaches can live despite this, as evolution created their intestines so that they can consume oxygen from the atmosphere. They can even live without water for short periods as long as they can burrow in mud.
Needless to say, dojo loaches aren’t picky about whether the water they live in is clear or cloudy.
In the wild, dojo loaches aren’t particular about having access to plants. Instead, they’re more concerned about having enough fallen plant material for burrowing and eating.
Dojo loaches can grow as big as one foot long in the wild. But in captivity, it’s common for them to average six inches.
Nevertheless, if you give your loach a larger-than-average aquarium and keep their diet in tip-top shape, you might see these creatures grow as big as 12 inches.
There isn’t a difference in length between male and female dojo loaches. The only notable size difference is the second pectoral ray, which is slightly longer in males.
Dojo loaches have a lifespan similar to a large dog, averaging seven to ten years. That’s a significantly longer time than many other tropical fish species.
It takes dojo loaches three or four years to reach their adult size.
You can expect them to grow until they reach about five inches long. After that time, their growth slows significantly.
Generally speaking, the larger the space you give your dojo loaches and the better quality food you give them, the longer you can expect them to live.
It’s challenging—but not impossible—to tell male and female dojo loaches apart.
The second pectoral ray on males has a longer and more triangular shape than on females.
So, if you only have one dojo loach or loaches of the same gender, someone with an untrained eye likely won’t be able to determine the gender.
Despite their rather scary look to some, given their eel and snake-like appearance, dojo loaches are peaceful fish. In fact, they’re beyond friendly—these social fish must have other dojo loaches in their tank to remain emotionally healthy.
Dojo loaches also get along well with other fish species. They shy away from aggressors, preferring to hide than put up a fight.
Owning dojo loaches is a joy because they’re playful fish. They’re also intelligent and can bond with their fish keepers, sometimes eating food straight out of their hands.
You should aim to keep a minimum of three dojo loaches in the same tank for their emotional well-being.
Both male and female dojo loaches are equally peaceful and playful. They’ll even try playing and hanging out with other fish in their tank.
The biggest mistake new fish keepers make with dojo loaches is assuming the tank parameters don’t matter, given their hardiness. But following the recommendations below is vital for ensuring your dojo loach lives to their maximum lifespan.
Minimum Tank Size
Between their large size, enjoyment of exploration, and need to live in groups, the minimum size tank you should buy for three dojo loaches is 100 gallons.
Furthermore, ensuring the tank has a lot of bottom surface area is vital since loaches spend most of their time in the substrate.
Therefore, you should ensure your dojo loach tank is at least four feet long.
Most aquariums come with lids, but double-checking that’s the case for the tank you want to buy is vital. That’s because dojo loaches are natural jumpers.
So, unknowing fish keepers have sometimes encountered their loaches on the floor beside their aquarium. Luckily, that’s not always a death sentence, given that dojo loaches can “breathe” oxygen in the air.
Once you purchase your tank, the next step is to prepare the water for your new dojo loaches.
Dojo loaches prefer cooler water than most tropical fish, tolerating temperatures between 50°F and 75°F.
But within this range, they prefer their water on the cooler end.
If dojo loaches spend too much time in warm water, they often experience a significant reduction in lifespan.
Dojo loaches can handle pH levels from 6.5 to 8.0.
So, these fish lean towards a slightly more alkaline environment. But using a pH testing kit to get the water’s pH in the middle of this range is ideal for keeping your dojo loaches in optimal condition.
Dojo loaches don’t need salt in their tank because they’re a freshwater species.
However, salt can be helpful when treating certain parasites and diseases. Should you decide to treat your dojo loach’s tank with salt, be sure to purchase an aquarium variety.
Otherwise, the iodine in table salt could kill your fish.
Now that you have your water parameters ready, it’s time to arrange your tank so that it’s a pleasant environment for your dojo loaches and aesthetically pleasing for you.
Since it’s unlikely you want to use mud and decaying leaves as your tank’s substrate, fine sand is the next best option.
As bottom feeders, dojo loaches will spend much of their time digging through the bottom of their tank in search of food. They’ll also burrow into the substrate to rest.
Therefore, providing them with a soft substrate is crucial so that they don’t acquire scratches, opening the opportunity for infections.
Lots of decorations aren’t vital for dojo loaches since they’re often more concerned with the substrate. However, adding some logs at the bottom of their tank is a great way to mimic their natural habitat.
These logs will also offer your loaches hiding spaces. Hiding spots are especially important if you have other fish species in the tank.
You’re also welcome to add decor that’s pleasing to you.
Just be sure not to overdo it on the decoration front, as dojo loaches need plenty of space at the bottom of their tank for swimming and burrowing.
Including live plants in your dojo loach’s aquarium is a tricky topic—your fish will appreciate them, but they’ll also accidentally dig them up if you’re not careful.
Using tall, sturdy plants like hornwort is an excellent choice for dojo loaches.
However, you’ll need to anchor the plants well. Otherwise, you’ll find them floating at the water’s surface from your loaches’ burrowing activities.
As nocturnal fish, dojo loaches don’t have a major preference for lighting other than wanting the lights off at night.
But before you get disappointed at being unable to watch your loaches be their playful selves, know this: You can install a red or blue light.
Red and blue lights allow humans to watch their nocturnal fish explore their tank without disturbing the fish’s waking habits.
That said, there’s nothing wrong with having a regular aquarium lamp on during the day.
In fact, standard light is beneficial if you want to breed dojo loaches. Since these fish breed in the winter, they rely on shorter daylight hours to know when they should spawn.
Filters are a blessing and curse for dojo loaches. They keep toxic wastes out of the water to keep your fish healthy, but if you don’t tap the bottom of the filters, your loaches may enter them and become stuck.
For this reason, using a sponge or filter media is vital to remove any openings that your dojo loaches could wander into.
A high-quality filter keeps ammonia, nitrate, and other deadly toxins out of the water.
Several filter options exist on the market. We recommend one that has a minimum of mechanical and biological properties.
But chemical filters are also helpful for controlling harmful wastes.
Since dojo loach tanks are so large, buying a filter with a large canister is best. That way, it reduces the number of times you need to empty it.
Dojo loaches don’t require a heater. In fact, you’ll be doing them a disservice if you purchase one, assuming the temperature in your home doesn’t drop below 50°F.
Despite originating from a semi-tropical region, dojo loaches prefer cool water.
Dojo loaches are omnivores, meaning they eat both plant and animal protein. But of the two, they gravitate towards plants, mainly algae.
Some excellent options for feeding your dojo loaches include:
- Algae wafers
- Sinking pellets
- Tubifex worms
- Insect larvae
If you have live plants that have brought snails into your aquarium, you can expect your dojo loaches to eat both the plants and the snails.
But these fish aren’t ideal for keeping snail populations in check, given that they’re slow eaters.
Although dojo loaches can learn to surface at the top of the tank to take food straight from your hand, they likely won’t do so if you have other fish species in the tank that congregate there.
So, it’s best to rely on sinking pellets if your dojo loaches have tank mates to ensure they get enough food and nutrients.
We recommend feeding your dojo loaches two or three times per day. Follow the instructions on the sinking pellet label to determine the amount of food to give your fish according to their size.
Then, supplement with live food on top of that to keep your fish in tip-top health.
It’s challenging to breed dojo loaches in captivity. They rely on feeling the water temperature cool down during winter to prepare their bodies to spawn in the spring.
Therefore, to breed your dojo loaches, you must gradually turn down their water temperature and decrease daylight hours to mimic the winter.
Then, you must slowly increase the water temperature and daylight hours to spark spring-like conditions.
At that time, the male will wrap his body around the female, fertilizing her eggs as she lays them. Females lay around 50 eggs, fewer than many other tropical fish species.
Moving the eggs to a different tank after this happens is best. Otherwise, the parents may eat them.
Baby dojo loaches hatch quickly, emerging from their eggs after only three days.
Another strategy you can try if you want your dojo loaches to breed is by performing a significant water change with two or three-degree cooler water.
Not only does the temperature change spark dojo loaches to breed, but the water movement makes the fish think of the rainy season that comes with the spring.
You must take care if choosing this method, though, for changing too much water too drastically can shock your dojo loaches, creating health problems.
Despite their hardy ways with water quality, dojo loaches have a higher chance of getting parasites and diseases than many other tropical fish species.
Part of this is because they have thin, small scales. Therefore, they have less protection from viruses, bacteria, and fungi.
Below are some of the most common diseases that dojo loaches face.
Bloating is a condition in dojo loaches that can have several instigators.
In some cases, the bloating could be from eating too much or lots of dry food. Other times, it can be a symptom of a parasitic infection or constipation.
People sometimes refer to bloating as swim bladder disease. What makes this condition so hard to treat is that you might have to use trial and error to see what medicine your fish responds to, according to the condition’s culprit.
Whereas some tropical fish can ward off the ich parasite on their own, dojo loaches commonly fall victim to ich’s wrath.
Identifying ich is easy, given that your loaches will have tiny white spots on their bodies. They’ll also scratch themselves against hard objects.
Treating ich is a long-term ordeal, given that the medicine only works to kill it in one stage of the parasite’s life cycle. You should also gradually and temporarily raise the water’s temperature.
Skinny disease is the common name for chronic wasting syndrome, which is a similar condition that land animals experience.
The disease originates from parasites, causing dojo fish to lose extreme weight for their size.
You can treat skinny disease by performing frequent 30% water changes, adding some aquarium salt to the water, and applying medication. It’s also imperative to quarantine your loach if the parasite doesn’t appear to have affected other tank members.
Potential Tank Mates
Dojo loaches make excellent tank mates since they’re so peaceful. But given that they enjoy cool water temperatures, there are limitations on the types of species you can pair with them.
Some examples of excellent tank mates for dojo loaches include:
- Comet goldfish
- Bloodfin tetra
- Hillstream loach
- Buenos Aires tetra
The size of your dojo loach’s tank mates is an important consideration.
Given that dojo loaches are omnivores, their peaceful nature can’t override their ability to see small tank mates as snacks if hunger strikes.