Bob is on hand to advise one of our readers on the aquarium care requirements for sumo loaches.
I would like to keep some sumo loaches in a 90x38x38cm (36x15x15”) fast-flow aquarium. How many should I keep to spread out any territorial issues? Also, what non-bottom dwellers could I keep with them please?
BRYAN TAYLOR
Bob's advice on sumo loaches:
A couple of closely related fish from the genus Schistura are available as sumo loaches. They differ slightly in the number of 'belt' bars around their middle, and the colouration around them, but their care is much the same. Schistura balteata is the 'true' sumo loach, while the more colourful tri-band sumo (Schistura cf. balteata) is becoming more available too.
Natural habitats of sumo loach
These fish come from fast-moving rivers and streams in Myanmar. The water is clear, full of oxygen and often shaded by the surrounding trees. The substrate is a mix of course sands and gravel and larger rocks and boulders provide shelter.
Aquatic plants are absent, but some of their habitats do feature marginal plants. You could utilise these to add some greenery to the aquarium. You could utilise Java ferns tied to the largest boulders at the water line to replicate this. These epiphyte plants will help to provide extra shade for your loaches.
Aquarium care
These loaches will do best in a tank that replicates their natural habitat, so your aquarium sounds ideal. A slightly cooler temperature of around 22°C (72°F) would be my recommendation. This will help to keep dissolved oxygen levels a little higher. Opt for an oversized filter, or a powerhead, to mimic the fast water flow.
Aim for water parameters that are slightly soft and acidic. A pH of 6-7.5 and a hardness below 12°H should work well. Fishes from flowing water habitats are often more susceptible to nitrates, and sumo loaches are no exception. Excellent filtration and regular water changes are a must for this species to thrive.
Related article: Homemade high flow, shallow river tank.
Compatibility of sumo loaches
These fish can be a little aggressive to each other when kept in small groups. You can alleviate this by making sure there are plenty of hiding places and décor to break up lines of sight. This allows the fish to find their own territory without needing to constantly harass their fellow sumo loaches.
Although single specimens and known pairs can work for smaller aquariums, group housing in a spacious home is also a great option. Aim for at least ten loaches to spread any aggression.
With regards to other tank mates, I'd stick with a loose Asian theme and try danios. The classic zebra danio (Danio rerio), would enjoy this set-up. Plus, you'd get to see a new dimension to this aquarium staple.
If you're after something a little less common, then there are a couple of alternatives. The gold-ring danio (Danio tinwini), or the orange-finned danio (Danio kyathit), will both thrive in your tank. All these will do best in groups of eight or more and should be a constant source of movement in the tank as they swim against the moving waters.
Related article: Finding the perfect loach for a planted aquarium.
Sumo Loach Factfile
Scientific name: Schistura balteata
Size: Can reach up to 9cm (3.5").
Origin: They occur around the Tenasserim mountain range that sits between Myanmar and Thailand. Different populations occur on either side of the mountains, and a handful of new species have been described.
Habitat: Inhabits fast flowing, well oxygenated streams that are devoid of aquatic plants.
Tank size: 90x30x30cm (36x12x12”).
Water requirements: A pH of 6.0-7.5, and a hardness below 12°H
Temperature: 2-26°C (72-79°F).
Temperament: They can be territorial, although with enough space and decor groups can live together. They generally leave midwater species alone so shoaling fish that live in similar flowing habitats can work well as tank mates.
Feeding: An omnivore but shows a preference for small insect larvae, worms and zooplankton. Feed plenty of frozen and live foods along with a staple dry sinking food. Frozen brineshrimp enriched with spirulina can work well, introducing some plant matter into their diets.
Availability & cost: Occasionally seen in stores, and your local fish shop should be able to order them if you ask. Prices tend to start at around £6 each.