Fish, Tanks and Ponds

Fish, Tanks and Ponds
A comprehensive guide to fish

Yasuhikotakia modesta

Red finned loach

Red finned loach, Yasuhikotakia modestaRed finned loach, Yasuhikotakia modesta
Photos by Andy Rapson

General Notes:

Although wild specimens can grow up to 25cm (10 ins) captive specimens rarely exceed 17.5 cm, (7 ins). Red finned loaches are nocturnal by nature but most will adjust after a short time and come out to feed during the day time. It is important to use a soft substrate like fine sand to prevent damage to their delicate barbels. They love to dig in the substrate looking for food items, due to their size and strength this means that most real plants won't thrive in their tank.
Unfortunately this species is one of the ones targeted by the dyed fish trade. Fish which have been dyed are far more likely to suffer poor health and die prematurely.

  • Dye is injected in to the fish. Some dealers will 'out of ignorance' tell customers that the colour comes from a special food.
  • If asked for this special food they will of course be told something like it is only available to commercial breeders.
  • The same needle is used over and over again passing any infection from on fish to another. Until the needle becomes to blunt to use.
  • The dye used will have faded away after a few months if the fish lives that long.
  • Please don't support this trade and refuse any fish which have been dyed.


Wild red finned loaches feed at night on worms, crustaceans and insects. In captivity they are greedy eaters and will accept small earthworm, chopped prawns, shell fish, blood worms, sinking pellets of a suitable size, algae wafers and flake food. Feed them just before the aquarium lights are turned off initially, they will eventually learn to come out to feed during the day time.


Red finned loaches are big strong fish and they are quite boisterous. It is likely that delicate fish such as Discus would be intimidated by them so only keep them with other lively species of a similar size such as medium sized barbs. Red finned loaches tend to live in groups with a strong pecking order and they will be seen at their most natural by keeping them in a small group of about five individuals. Once they have established a pecking order they will live quite happily along side each other.


Unknown, there are no reliable external differences between the sexes.


This species has a complex breeding pattern which involves the fish migrating at certain times of the year in order to spawn. Red finned loaches have not been bred by hobbyists yet.

Wild status

The red finned loach has a wide distribution. It is heavily fished for the aquarium trade but the impact of this is uncertain without more research. Given the wide distribution, it is assessed as Least Concern by the ICUN Red List of Endangered Species at present.

Additional information

This whole family of fish is prone to having the very rare rogue among its numbers. Very very occasionally a fish will be noticed missing an eye. Invariably there is usually a Botia type loach in the tank when this happens usually at night. If this happens to one of your fish the only solution is to rehouse the loaches or there is a very real chance of a repeat. I must stress this is very rare but it is better to know in advance just in case.

Information at a glance

pH: 6.5 - 7.5
dGH: 4 - 12
Temperature: 22 - 28°C (72 - 82°F)
Diet: Omnivore
Size: 25cm (10in)
Min tank size: 675 litres
Difficulty level: Intermediate
Aquarium type: Community
Swimming level: Lower

Distribution and habitat

distribution map for Red finned loach, Yasuhikotakia modesta

Origin: Asia: Mekong, Chao Phraya  and Mae Khlong basins

Habitat: Usually found in large rivers with a muddy substrate also occurs in flooded fields


Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Cypriniformes
Family: Cobitidae
Genus: Yasuhikotakia
Species: Y. modesta (Bleeker, 1864)

Other common names:
Red tail Botia

Synonyms: Botia modesta, Botia rubripinnis