Minimum Tank Size: 29 Gallons Minimum, 55 Gallons Recommended
Care Level: Easy
Water Conditions: 6.5-8 and Moderately Hard to Hard
Temperature: 50-72 F (10-23 C)
Maximum Size: 12 inches (30cm)
The weather loach (Misgurnus anguillicaudatus), also known as the dojo loach, is a hardy and friendly beginner fish that was originally found throughout Asia. In the wild, it is primarily a bottom dwelling scavenger, and has barbells similar to catfish that it uses to sift through detritus to find food on the bottom of ponds and shallow streams.
The name weather loach originates from the fact that these fish can detect barometric pressure changes before a storm. When the barometric pressure falls, the fish will become extremely agitated and will dart around the aquarium in the hours before a storm. While this isn’t terribly impressive in the age of the Weather Network, they were prized for this ability in ancient times and may have been kept domestically for nearly as long as goldfish.
In the home aquarium, weather loaches are one of the few “friendly” fish available. Many of them will actively seek out contact, and will readily accept food from their owner’s hand. While they shouldn’t be handled on a regular basis, a weather loach that feels safe will sometimes even swim up into your outstretched hand (which isn’t necessarily a good thing if you’re squeamish around anything snake-like.)
Weather loaches tend to be a messy fish that constantly roots around in the substrate. Because of this, they should always be housed in a spacious aquarium, with strong filtration.
When choosing a filter, a high quality Hang-on-back filter is an excellent choice, and can be combined with a sponge filter for extra filtration (Click here for HOB filter reviews). If you can afford the hefty price tag, a canister filter is the best choice, since some weather loaches enjoy jumping or crawling up into a hang-on-back filter. While these fish are usually fine, it can lead to a few hours of frantic searching for the missing loach.
And filters aren’t the only escape route for weather loaches. Throughout the hobby they are well known for being escape artists. Any aquarium housing them should have always be covered, any openings sealed with breathable material. If a weather loach does manage to jump out of the tank, they can still survive for several hours. Even one found on the floor that looks completely dried out, should be placed back in the aquarium to see if it recovers. There are numerous stories of dried out loaches being found on the floor, and miraculously springing back to life once they were placed back in the water.
The water in a weather loach tank should be kept cool and should never be heated unless the room falls below 50F (10 C). While weather loaches can be kept in tropical aquariums, it will greatly shorten their life spans. A well cared for loach will live for close to 10 years in a cold water aquarium, but will usually live under 4 years when kept in a tropical aquarium.
The ideal substrate for weather loaches is sand or other loose, easy to dig material. They love to dig in their substrate, and will often bury themselves up to their necks, presenting their owner the view of a group of small heads poking out of the sand. When threatened, weather loaches will disappear into the substrate, and newly purchased fish will often “disappear” for a few days, only to reappear draped across a decoration a few days later.
Weather loaches are social fish, and you should always keep in groups of at least three. If they are kept on their own, they will spend most of their time hiding, and will rarely be active during the day. When they are kept in a group, their behavior completely changes – they will constantly swim around the tank, and will often sit out in the open in a “pile” of weather loaches. The don’t seem to mind piling on top of each other, and this will lead to comical positions where all the loaches are stacked up into a big loach pyramid.
In the wild weather loaches are omnivores, and much of their diet is made up of algae and plant material at the bottom of ponds and shallow streams. They will also opportunistically feed on insects, snails and small invertebrates.
In the home aquarium, this can be mimicked by feeding them a spirulina based pellet or flake, and a high quality flake food. One of the best prepared foods for them is New Life Spectrum Community Formula Sinking. They should also be fed frozen foods as a treat, with their favorites being tubifex or blackworms, bloodworms and daphnia.
If you don’t have access to a spirulina based food, they can also be fed vegetables on a regular basis. The most readily accepted vegetables are blanched zucchini medallions, shelled peas and cucumber medallions. It doesn’t take long for a few adult weather loaches to devour a whole zucchini medallion, but you should still remove any uneaten vegetables after 24 hours. This helps to prevent it from rotting and fouling the aquarium water.
Since weather loaches are cool water fishes, they require a trigger to start the breeding process. This can be accomplished through keeping the weather loaches in a room that has low temperatures in the winter and spring, and changing the amount of light that they receive in the spring. Lighting in their tank should be reduced in the winter, and slowly increased in the spring until they are getting a minimum of 12 hours of light in the aquarium.
When breeding is triggered in the weather loach, the male will begin to court the female which can last several hours. He will then wrap himself around the female until the eggs are released, and then fertilize them.
The eggs will generally hatch within a few days, and the fry are so small that they will have to fed infusoria or special commercial fry food for up to a week. After this, they can be fed baby brine shrimp and powdered spirulina pellets.