Flying fox
Epalzeorhynchos kalopterus
Care at a glance
- Temperature
- 68–79°F (20–26°C)
- pH
- 6.5–7.5
- Adult size
- 6.3 in (16 cm)
- Minimum tank
- 37 gal (140 L)
- Temperament
- Mostly peaceful
- Social behavior
- Solitary
- Swim level
- Bottom
- Difficulty
- Medium
- Breeding
- No record
- Rarity
- Common
- Origin
- Thailand, Malaysia
- Family
- Cyprinidae
Overview
This is a solitary, mostly peaceful bottom dweller that gets territorial as it grows, especially toward its own kind and similar-shaped fish. Keep one per tank unless you have a lot of space. It needs that 140 liter minimum, water in the low to mid 20s C, and pH from 6.5 to 7.5. It grazes algae and biofilm but also wants sinking foods, frozen items, and blanched vegetables. Pick robust tankmates that are not slow or long-finned.
In the wild
The flying fox comes from fast, clear forest streams in Thailand and Malaysia, the kind with rocky beds and a steady current. Those streams stay well oxygenated and run slightly acidic to neutral. At home, give it room over a 140 liter tank, smooth rocks and wood to graze on, good flow, and clean water. Aufwuchs, the film of algae and tiny life on surfaces, is a big part of what it eats in the wild.
Good to know
Epalzeorhynchos kalopterus is a cyprinid in the family Cyprinidae, reaching about 16 cm as an adult, larger than people expect from the slim juveniles sold in stores. It has the barbels and underslung mouth typical of bottom-grazing cyprinids. Breeding in aquariums is essentially unrecorded, and the fish in the trade are wild-caught or farmed rather than home-bred.
Did you know
The flying fox is often confused with the Siamese algae eater, and the two get sold under each other's names. The quickest tell is the black side stripe: on a true flying fox it ends in a clean line with a gold band above it, while the Siamese algae eater's stripe is more ragged and runs into the tail. Knowing the difference saves you from buying the wrong fish for an algae job.
Where to buy
Some links may not be the exact species or variety.
- Aquatic Arts Freshwater fish, shrimp and snails with an arrive-alive guarantee
- Aqua Huna Freshwater fish, shrimp and plants with a three day live arrival guarantee
…or ask your local fish store.
Appears in
Freshwater fish · Freshwater sharks · Bottom dwellers · Algae eaters
Keeping Flying fox?
Track water tests, reminders and stocking fit.
Related species

Rainbow shark
Epalzeorhynchos frenatum5.9 in (15 cm)32 gal (120 L)68–79°F (20–26°C)
Red-tailed black shark
Epalzeorhynchos bicolor4.7 in (12 cm)30 gal (115 L)68–79°F (20–26°C)
Silver flying fox
Crossocheilus reticulatus6.3 in (16 cm)53 gal (200 L)64–77°F (18–25°C)
Siamese algae eater
Crossocheilus oblongus6.3 in (16 cm)37 gal (140 L)68–79°F (20–26°C)
Cambodian log sucker
Garra cambodgiensis5.9 in (15 cm)32 gal (120 L)68–81°F (20–27°C)
Panda Garra
Garra flavatra3.5 in (9 cm)26 gal (100 L)72–81°F (22–27°C)
