Shen’s River Loach
Hemimyzon sheni
- Care level
- Specialist
- Adult size
- 4.9–7 cm
- Minimum tank
- 80 litres
- Temperature
- 18–25 °C
Species profile
Serpent Loach
Serpenticobitis octozona
Common names: Serpent Loach
Recognized speciesLoaches
Adult size
Up to 6 cm
Typical adult length 4.2–6 cm.
Up to 6 cm
Countries of origin
Good fit for your tank?
Good fit for
- Keepers able to provide at least a 60 cm aquarium with the substrate, current, and cover this loach needs.
- A mature aquarium where bottom-feeding fish receive targeted food and regular maintenance.
Think carefully if
- The aquarium is shorter than 60 cm or cannot support the recommended social group.
- The aquarium has coarse substrate, unprotected filter gaps, or aggressive competition at the bottom.
Serpent Loach is a bottom-dwelling loach requiring a 60 cm or longer aquarium, suitable substrate, stable water, and species-appropriate social housing.
Appearance and Identification
A small elongate loach with eight prominent dark bars over a pale body and a snake-like profile.
Best maintained in a group in a clean stream-style aquarium.
Sexes are difficult to distinguish reliably outside breeding condition. Mature females may become fuller through the abdomen, while males of some species develop stronger colour, fin shape, or breeding tubercles.
Tank Requirements
- Suggested filter
- About 240–300 litres an hour
- Suggested heater
- About 50–100 W for this tank
- Minimum tank volume
- 60 litres
- Minimum tank length
- 60 cm
- Minimum group size
- 6
- Recommended group size
- 8
- Activity level
- Moderate
- Flow preference
- High
- Planting preference
- Lightly planted
- Hiding places
- Yes
- Lid recommended
- Yes
- Jumping risk
- Medium
Set up a mature aquarium at least 60 cm long with clean, well-oxygenated water, smooth gravel and sand, rounded rock piles, crevices, and a secure lid. Arrange several separate shelters and keep detritus from collecting beneath hardscape.
Behaviour and Tankmates
Serpent Loach is a bottom-dwelling stream loach that searches among stones and crevices for small prey. It may rest in cover, then move quickly into current or across the substrate when feeding.
Keep 6 to 8 where the species is peaceful and space permits. For more territorial forms, a single fish or carefully observed group in a larger footprint is safer.
Adults may defend caves, rock gaps, or feeding areas from similar-shaped fish. Provide broken sight lines and multiple retreats.
Choose peaceful or moderately active stream fish that share the same temperature and oxygen needs. Avoid tiny shrimp, slow bottom fish, and combining several territorial loaches in a small footprint.
Water Parameters
Maintain stable, clean water within the stated range. Oxygenation, low organic waste, and gradual acclimation are more important than forcing an exact pH or hardness value.
Parameter caveat
Match the supplier water during acclimation and change temperature or mineral content gradually. Rare wild-caught loaches may arrive adapted to narrower conditions than the general range suggests.
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Manual aquarium siphon and gravel cleaner
A manual siphon for routine aquarium water changes and accessible waste removal. The seller lists a hose approximately 1.6 m long.
Control the flow and keep the intake clear of fish and delicate planting. Clean the areas appropriate for your substrate and layout rather than disturbing the entire planted bed.
Daraz NepalCheck availability on Daraz
Feeding
- Diet types
- Carnivore, Insectivore, Omnivore
- Feeding frequency
- Daily
- Preferred foods
- Quality sinking carnivore or omnivore pelletsUse a small pellet suited to the fish’s mouth.
- Frozen insect larvae and crustaceansOffer varied foods such as bloodworm, cyclops, Artemia, or Daphnia.
- Live aquatic invertebratesUse occasionally for conditioning and natural hunting behaviour.
Offer small sinking foods rich in aquatic invertebrate protein. Combine a dependable prepared staple with frozen or live insect larvae, Artemia, Daphnia, or similar foods.
Feed small portions at more than one point because territorial fish may guard food in a confined area.
Breeding
- Breeding type
- Egg Layer, Egg Scatterer
- Breeding difficulty
- Difficult
- Breeding temperature
- 23 °C
- Breeding pH
- 6.8
- Brood or egg count
- Unknown or variable; species-specific aquarium counts are not dependable.
- Incubation
- 3 days
- Parental care
- None
- Baby foods
- Infusoria or cultured microscopic foodUse when newly free-swimming fry are too small for Artemia.
- MicrowormsIntroduce once fry actively search the bottom.
- Newly hatched Artemia naupliiUse after fry are large enough to swallow nauplii.
Captive breeding is poorly documented. The fish is expected to scatter or deposit small eggs among gravel, stones, or vegetation without parental care. Seasonal cooling or warming, increased flow, and live-food conditioning may be important, but claims should be treated cautiously unless documented for this species.
Habitat and Origin
- Geographic origin
- Asia, Laos, Southeast Asia
- Natural habitat
- Fast Stream, Freshwater Stream, Rocky Shoreline
- Aquarium contexts
- Freshwater Aquarium, High-Flow Aquarium, Species-Only Aquarium
- Audience level
- Specialist
Classification
- Profile type
- Recognized species
- Genus
- Serpenticobitis
- Family
- Serpenticobitidae
- Species group
- Fish, Loaches
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Skunk Loach
Yasuhikotakia morleti
- Care level
- Advanced
- Adult size
- 8.4–12 cm
- Minimum tank
- 140 litres
- Temperature
- 24–29 °C
Speckled Butterfly Loach
Beaufortia polylepis
- Care level
- Specialist
- Adult size
- 5.6–8 cm
- Minimum tank
- 80 litres
- Temperature
- 18–25 °C
Spined Loach
Cobitis taenia
- Care level
- Intermediate
- Adult size
- 9.1–13 cm
- Minimum tank
- 140 litres
- Temperature
- 10–24 °C