Epalzeorhynchus kallopterus 7 - (Epalzeorhynchos kalopterus) — 7-10cm

Overview

The algae eater fish Epalzeorhynchos kalopterus, commonly known as the flying fox fish, is a hardy, active algae-grazing cyprinid native to Southeast Asia, including parts of Thailand, Malaysia, and surrounding freshwater systems. With an adult size of up to 10 cm, this energetic species is prized for its utility as a freshwater algae eater and its lively swimming behavior. Available for sale UK from Tropical Fish Co, the flying fox is ideal for buy tropical fish UK enthusiasts seeking a functional, active addition to well-planned community aquariums. However, prospective owners must be prepared for its semi-aggressive temperament, territorial behavior with age, and potential for fin-nipping, making careful tankmate selection essential. This freshwater fish UK is best suited to larger, well-established aquariums with robust tankmates.

Appearance

Epalzeorhynchos kalopterus displays a streamlined, torpedo-shaped body with a golden-brown to tan base color and a bold black horizontal stripe running from the snout through the eye to the tail. The fins are typically yellow to reddish, with the pectoral and pelvic fins showing particularly vibrant coloration. The mouth is positioned ventrally with rasping lips adapted for algae grazing. The body is sleek and muscular, built for active swimming. Healthy specimens show clear eyes, intact fins, vibrant fin coloration, and active, alert behavior. Their bold stripe and colorful fins make them visually distinctive, though they are often confused with the true Siamese algae eater (Crossocheilus sp.), which has different fin coloration and temperament.

Natural Habitat

In the wild, Epalzeorhynchos kalopterus inhabits fast to moderate-flowing rivers, streams, and floodplains across Southeast Asia. The natural environment features warm, well-oxygenated water with rocky or gravelly substrates and abundant algae-covered surfaces. These fish graze on biofilm and algae growing on rocks, wood, and aquatic vegetation. Natural conditions include moderate to strong water flow, good oxygenation, and plenty of grazing surfaces. They are active, mid to bottom-dwelling swimmers that occupy areas with current and cover. Replicating these well-oxygenated, flowing conditions with ample grazing surfaces promotes natural behavior and reduces territorial aggression in this flying fox fish species.

Aquarium Setup

A minimum 120-litre aquarium is essential for Epalzeorhynchos kalopterus, with larger tanks strongly recommended to provide adequate swimming space and reduce territorial behavior. Use a soft substrate such as fine sand or smooth gravel. Provide plenty of driftwood, smooth rocks, and robust plants such as Java fern and Anubias to create grazing surfaces and visual barriers. The tank should have open swimming space with moderate water flow. Robust filtration with good oxygenation is important. A tightly fitted lid is recommended, as these active fish may jump if startled. Moderate to bright lighting encourages algae growth, providing natural grazing opportunities. The tank should have plenty of territory-defining décor to minimize aggression among individuals.

Water Parameters

Flying fox fish thrive in water with a pH of 6.0-7.5 and temperatures between 23-27°C. Maintain excellent water quality with weekly partial water changes of 25-30%, keeping ammonia and nitrite at zero and nitrate below 20 ppm. Soft to moderately hard water is preferred, replicating natural Southeast Asian river conditions. Use a reliable heater and thermometer to maintain stable conditions. Ensure good oxygenation with moderate filtration and gentle to moderate water flow. Stable, clean water conditions are critical for long-term health and to minimize stress-related aggression. Regular maintenance prevents common diseases and supports the fish's natural algae-grazing and active swimming behavior.

Feeding

Epalzeorhynchos kalopterus is primarily a herbivore and algae grazer, but should be offered a varied diet including algae wafers, spirulina-based foods, blanched vegetables such as zucchini and cucumber, and occasional protein-rich frozen or live foods such as bloodworms or brine shrimp. Feed once or twice daily in small portions. These fish will graze continuously on naturally occurring algae and biofilm, but do not rely solely on this—supplemental feeding is essential. Avoid overfeeding, which can degrade water quality. A varied, balanced flying fox fish diet supports healthy growth, maintains vibrant fin coloration, and ensures robust immune function. These active grazers help control algae but are not a complete algae solution.

Behaviour

Epalzeorhynchos kalopterus is an active, energetic species that spends most of the time swimming actively in the mid to lower water column, grazing on surfaces, and exploring the tank. Juveniles are generally peaceful, but as they mature, they can become territorial and may chase other fish, especially other algae eaters or similar-looking species. They may also nip fins of slower or long-finned tankmates. Despite their semi-aggressive tendencies, they are generally less aggressive than some other Epalzeorhynchos species and can coexist with appropriately chosen robust tankmates in spacious aquariums. Their active, lively behavior adds movement and energy to community setups, making them engaging subjects for observation.

Tank Mates

Ideal flying fox fish tank mates include robust peaceful community fish of similar size such as danios, barbs, rainbowfish, and gouramis. Avoid small shrimp and very small invertebrates (which may be harassed), slow-moving or long-finned fish (which may be nipped), other similar-looking algae eaters (which will be chased), highly territorial bottom fish, and very small fish that may be harassed. Multiple Epalzeorhynchos kalopterus should not be kept together unless the tank is very large (200+ litres) with ample territory-defining décor, as aggression is common. Many aquarists prefer to keep a single specimen to minimize territorial disputes. Their semi-aggressive nature requires careful tankmate selection and ample space.

Breeding

Epalzeorhynchos kalopterus breeding is uncommon in home aquaria and usually requires large, well-conditioned fish and carefully managed water conditions. Commercial breeding is not widely reported, and most aquarium specimens are wild-caught. If breeding is attempted, provide a very large tank, excellent water quality, seasonal conditioning with varied foods, and specific environmental cues. Little detailed information is available on spawning triggers or parental care. Breeding attempts should only be undertaken by experienced aquarists with appropriate facilities, patience, and specialized knowledge. Most home aquarists will not achieve breeding success with this species.

Why Buy from Tropical Fish Co

Tropical Fish Co is your trusted source for healthy, well-acclimatized algae eater fish for sale UK, including the active Epalzeorhynchos kalopterus. Each fish is quarantined, health-checked, and carefully acclimatized before dispatch, ensuring you receive robust, disease-free specimens ready to thrive in your aquarium. Our expert team provides personalized care advice, aquarium setup guidance, and ongoing support to help you succeed with these functional flying fox fish for sale. With secure packaging, next-day delivery across the UK, and a commitment to sustainable aquarium practices, Tropical Fish Co is the best place to buy tropical fish UK online. Whether you're seeking an active algae grazer or adding movement to your community setup, our flying fox fish deliver both utility and energy.