The Bengal Loach Botia dario is a stately looking fish from Bangladesh, and thus is suitably named. But we do like its alternate name the "Queen Loach" as being much more descriptive of its regal appearance.
This loach has a beautiful golden coloration with vertical black striping the length of its body and onto its tail. As this fish reaches maturity the stripes widen and the number of stripes increases, the overall coloration also becomes more subdued. It is also known as the Scarf Botia and as an Indian Loach in a more generic sense.
When you first acquire a Bengal Loach it may initially be shy. But if it is kept in good company (being several of its own kind) and has a comfortable home, it will soon spend time out and about. They are shy of bright light and will appreciate caves and plants as places to hide. They will retreat during the day and then get active towards dusk. They are great scavengers and they eat snails, so are good for snail control.
They are generally quite peaceful and though they may tussle with members of their own species, they don't really harm one another. They do well in a community aquarium with other less aggressive species, but they can hold their own with mildly aggressive tank mates.
A beautiful Queen Loach (a.k.a. Bengal Loach) swims among its tankmates.
Great video showcasing a wonderful and active Bengal Loach in a cool community tank. The Bengal Loach does great in a well planted and lit aquarium and can be kept with a number of other peaceful "river" fish, as demonstrated in this video. The video really shows off the active and energetic nature of the Bengal Loach!
The Bengal Loach Botia dario was described by Hamilton in 1822. It is found in northern India in the streams and rivers of Bangladesh. This species is listed on the IUCN Red List as least concern (LC). Botia dario is the most common of all Botia species and is also very widespread. There are threats to its habitats and it is heavily harvested for the ornamental trade. However the species is hardy and is therefore assessed as Least Concern at this time. Other common names it is known by are Queen Loach, Scarf Botia, and Indian Loach.
In the wild the Bengal Loach can grow up to 6 inches. It feeds on insects, larvae, crustaceans, and some plant matter. Although it primarily lives in streams and rivers, there is always a constant flow of water in its native region so the waters its habitat will fluctuate. During the monsoon as much as 15 feet of rain can fall, creating a series of shallow lakes. This species will migrate to these lakes to look for food sources. After the monsoon season has past, the continuously melting glaciers of the Himalayas feed into the streams and rivers and it then moves back into these waters.
Scientific Name: Botia dario
Social Grouping: Groups
IUCN Red List: LC - Least Concern
The Bengal Loach is a fairly small loach in the aquarium, but with a beautiful body color. In the wild they can get up to 6 inches (15.2 cm) in length. However they only reach about 2 1/2 inches (6.5 cm) in the aquarium, with a lifespan of about 5 - 8 years. Its body is golden overall with 8 to 10 vertical black cross bands, sometimes connected in places. The banding starts just behind the eyes and extends all the way onto the tail fin. In the adult the color patterning becomes more subdued, the cross bands widen and their number can increase.
This species is similar in appearance to the Ladder Loach Botia geto and the Hora Loach Botia dayi. However each species differs in patterning, somewhat in size, and in the shape of the head. Here are some of their distinctions:
The Botia dario has a sloped, rounded head, and is marked with 8 to 10 dark cross bands on the body that may be connected horizontally in places.
The Botia geto has a steep angular forehead. It has 8 to 10 dark cross bands as well, but they can be either paired or single. It also has light eye-spot like areas along the lateral line.
The Botia dayi is larger than either of the other two, reaching up 4 inches (10 cm) long in the aquarium. It has about 10 paired cross bands that may be connected, but only those in the dorsal region.
Size of fish - inches: 6.0 inches (15.19 cm) - This fish can reach up to 6 inches (15.2 cm) in the wild, but they only reach about 2 1/2 inches (6.5 cm) in the aquarium.
Lifespan: 8 years - This fish has a lifespan of about 5 - 8 years.
Fish Keeping Difficulty
The Bengal Loach can be hardy under the right conditions. However they are not recommended for beginners because of their need for pristine water and they do not have scales. Do not try to introduce these fish into biologically immature tanks. Not having scales make them more prone to disease and very sensitive to medications used to treat disease. Experience in treating scaleless fish is very important to be able to give your loach a healthy and long life
Aquarium Hardiness: Moderately hardy
Aquarist Experience Level: Intermediate
Foods and Feeding
Since they are omnivorous, this Queen Loach or Scarf Botia, will generally eat all kinds of live foods. They like tablets and frozen foods as well, but flake foods are not suggested. Feed brine shrimp (either live or frozen), mosquito larvae, tubifex, daphnia, and some vegetable foods such as algae wafers. It is also good to feed then cucumber, melons and blanched spinach. These loaches will also eat snails, so can help to keep those populations in check.
Diet Type: Omnivore
Flake Food: Occasionally - Rarely, flake foods are not suggested.
Tablet Pellet: Occasionally
Live foods (fishes, shrimps, worms): Half of Diet
Vegetable Food: Some of Diet
Meaty Food: Most of Diet
Feeding Frequency: Several feedings per day
The most important thing for these loaches is that they always have clean and well-oxygenated water. Frequent water changes of about 30% a week are needed for the Bengal Loach. With your weekly water change make sure to vacuum the gravel to remove all excess food and waste. Make sure not to remove the bio film on rocks, decor or no viewing panes of the tank. A magnet algae cleaner normally does a great job in keeping the viewing pane clear.
Water Changes: Weekly - Water changes of about 30% weekly.
The Bengal Loach will swim mostly on the bottom of the aquarium. Never introduce the Bengal Loach into a biological immature setup as these fish require pristine water. Because these fish do best in groups, a larger tank of at least 30 gallons will work best. They do best in soft, slightly acidic water with subdued lighting. They also need good water movement that provides plenty of oxygenation. The tank water should turnover at least 10-15 times per hour. Using an over sized external power filter will help meet that requirement. Powerheads and airstones can also be used to achieve proper flow and oxygenation and will also help prevent anything from being left unclean on the bottom.
It is recommended to have a tank set-up that resembles its natural habitat, slow to moderate moving rivers. The tank needs to have ample hiding places for this shy fish. Because they are burrowers, the substrate needs to be a fine smooth gravel or sand that does not have sharp edges. Provide hardy plants, like Java Fern, with the roots protected.
Make sure there are no sharp edges in the tank, these loaches like to wedge into tight areas. Larger smooth rocks can be used as hiding places. Driftwood and branches can also be added to provide shade and places for quick retreat. Plastic tubes also make safe and excellent hiding places. Be sure to have ample smooth surfaces to encourage bio film to grow. Have all decor firmly placed on the glass bottom so they don't fall over from their burrowing activity.
Minimum Tank Size: 30 gal (114 L)
Suitable for Nano Tank: Sometimes
Substrate Type: Sand/Gravel Mix
Lighting Needs: Low - subdued lighting
Temperature: 79.0 to 84.0° F (26.1 to 28.9° C)
Range ph: 6.5-7.5
Hardness Range: 5 - 10 dGH - They do best in soft, slightly acidic water with a hardness of up to about 10° dGH.
Water Movement: Moderate
Water Region: Bottom - These fish are mostly bottom dwellers, but will occasionally swim in the middle or upper parts of the aquarium.
The Bengal Loach is a good community fish. They can get a bit aggressive to members of their own species, but they don't harm each other. It is most likely an establishing of a hierarchy.
They are peaceful but they can hold their own with mildly aggressive tank mates. Though they hide during the day, and then are lively and active in the evening. If they are kept with aggressive tank mates, especially large predatory catfish, they will hide in the substrate. These loaches are known to nip at slow moving long finned fish.
Same species - conspecifics: Yes - These fish will be less shy if kept in a group.
Peaceful fish (): Safe
Semi-Aggressive (): Monitor
Aggressive (): Threat
Large Semi-Aggressive (): Threat
Large Aggressive, Predatory (): Threat
Slow Swimmers & Eaters (): Monitor - They are known to nip at slow moving, long-finned fish.
Shrimps, Crabs, Snails: Threat - is aggressive
Sex: Sexual differences
Full grown females will be rounder.
Breeding / Reproduction
Not much is known about the breeding habits of these loaches, and they are not yet bred commercially.
Ease of Breeding: Unknown
Loaches are more susceptible to disease than other aquarium fishes. This may have to do with the faint body scales and no head scales. So take caution when introducing these fish to an established tank. They are also very sensitive to different medications used to treat many diseases; a separate hospital tank is needed. Cold water and condition changes can also cause stress to this fish which makes them even more prone to disease.
Most common disease that affects this loach is Ich. Ich is short for Ichthyophthirius, also known as "white spot disease". It is a parasite that can attack nearly all aquarium fishes, but you'll find that loaches are often the first to be attacked. Take great care in treating ick as loaches are very sensitive to the medications used to treat it. Often the dose is half of what is normally used.
The second most common thing that affects loaches is a thing called skinny disease. This can be diagnosed fairly easily. If your loaches are eating a nitrous and healthy amounts and still seems to loose weight it is a good chance it has skinny disease. This is caused by internal parasites and can be treated with medication if used carefully.
An outbreak of disease can often be limited to just one or a few fishes if you deal with it at an early stage. When keeping these sensitive types of fish, it is common to catch deteriorating water conditions and disease before other fish are affected. The best way to proactively prevent disease is to give your Batik Loach the proper environment and give them a well balanced diet. The closer to their natural habitat the less stress the fish will have, making them healthier and happy. A stressed fish will is more likely to acquire disease.
Anything you add to your tank can bring disease to your tank. Not only other fish but plants, substrate, and decorations can harbor bacteria. Take great care and make sure to properly clean or quarantine anything that you add to an established tank so not to upset the balance. It is recommended to read up on the common tank diseases. Knowing the signs and catching and treating them early makes a huge difference. For information about freshwater fish diseases and illnesses, see Aquarium Fish Diseases and Treatments.
The Bengal Loach, also called a Queen Loach or Scarf Botia, is usually available.
Mark - 2014-12-01 We have two Bengal loaches in our 30 gallon community tank. They're full grown, the larger one about 5' and the smaller one about 4'. Healthy, active fish. IF it can be said that fish can exhibit traits that indicate a 'personality', our two loaches most certainly have personalities. They are active, playful, even mischievous. We originally bought them because of their reputations as being great at controlling snails. Since introducing them into our tank, I never see snails anymore. They like to hang around the corners of the tank, balancing on their tails. When the tank gets a little too peaceful, they'll chase around some of the other fish. Never mean spirited, just playful. Nice fish. Fun to watch. We would recommend that they are bought in at least a pair. They like to interact with each other. A single loach may get 'lonely', in a fish way.
Mark - 2014-12-16 This is a reply to my original message. The loaches are 5' and 4' in length, NOT 5' and 4'. That would be something to see.
Sherri - 2005-10-20 I have 2 Bengal loach's and they are awesome little fish. They are very adaptable and hardy. It is great to watch them playing and picking at each other constantly, they are fun to watch. They do good with their tank mates...I have 5 tiger barbs, 4 gouramis and 2 pleco's with them in a 30 gallon tank.