Glass catfish (Kryptopterus bicirrhis) — 7-9cm

Overview

The glass catfish Kryptopterus bicirrhis, also known as the transparent catfish or ghost catfish, is a striking, translucent schooling fish native to Southeast Asia. With an adult size of just 4.5 cm, this delicate species is one of the most unusual and visually captivating catfish for sale UK. Unlike most catfish that are bottom-dwellers, glass catfish are active midwater swimmers that school together in calm, dimly lit aquariums. Available from Tropical Fish Co, Kryptopterus bicirrhis is prized for its ghostly, see-through appearance, peaceful temperament, and fascinating schooling behavior. This freshwater fish for sale UK is ideal for enthusiasts seeking a unique, elegant addition to peaceful, planted community setups. Note that many fish sold as K. bicirrhis are actually the smaller species Kryptopterus vitreolus (ghost glass catfish).

Appearance

Kryptopterus bicirrhis displays a slender, laterally compressed body with remarkably transparent skin and flesh, allowing the internal skeleton and organs to be clearly visible. The body is colorless to pale translucent with a faint silvery sheen. The head is small with large eyes and two long, sensitive barbels extending from the upper jaw. The anal fin is long and continuous, running along most of the ventral surface, while the dorsal fin is reduced to a small ray. The tail is forked. Healthy specimens show clear, intact fins, smooth transparent skin, and active, coordinated schooling behavior. Their unique translucent appearance makes them one of the most visually stunning transparent catfish species available.

Natural Habitat

In the wild, Kryptopterus bicirrhis inhabits slow to moderate-flowing rivers, streams, and floodplains across mainland Southeast Asia. The natural environment features warm, slightly acidic to neutral water with heavily shaded areas created by overhanging vegetation, submerged wood, and leaf litter. These fish school in the midwater zone, often hovering in calm, dimly lit areas with gentle water flow. Natural conditions include subdued lighting, calm water, and plenty of cover. Replicating these conditions in captivity—especially dimly lit, calm, well-planted aquariums—is essential for reducing stress and encouraging natural schooling behavior in these delicate ghost catfish.

Aquarium Setup

A minimum 100-litre aquarium is essential for a school of Kryptopterus bicirrhis (ideally 6-10+ individuals). Use a soft, fine substrate such as sand. Provide plenty of hiding places and visual barriers using driftwood, smooth stones, and dense plant cover such as Java fern, Amazon sword, Cryptocoryne species, and tall background plants. Floating plants like water sprite or Amazon frogbit help diffuse lighting and create shaded areas. Gentle filtration with minimal water flow is essential, as these fish do not thrive in strong currents. A tightly fitted lid is recommended, as they may jump if startled. Subdued lighting is critical—bright lights stress the fish, cause them to hide, and prevent natural schooling behavior. The tank should be calm, dimly lit, and heavily planted.

Water Parameters

Glass catfish thrive in water with a pH of 6.0-7.5 and temperatures between 22-28°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 gentle filtration and good oxygenation, avoiding strong surface agitation or water flow. Kryptopterus bicirrhis is sensitive to poor water quality and sudden parameter changes, which can cause stress, reduced appetite, and increased disease susceptibility. Stable, clean water conditions are critical for long-term health and glass catfish lifespan.

Feeding

Kryptopterus bicirrhis is an omnivore with small meaty feeder tendencies. Offer a varied diet of quality micro pellets, frozen or live foods such as bloodworms, daphnia, brine shrimp, and small insect larvae. Feed small portions once or twice daily, ensuring food is consumed quickly and reaches the midwater zone where these fish feed. Avoid overfeeding, which can degrade water quality. These shy, slow feeders may struggle to compete with more aggressive tankmates, so ensure they receive adequate food. A varied, balanced glass catfish tank mates diet supports healthy growth, maintains transparency, and ensures robust immune function. Their delicate nature requires careful feeding management.

Behaviour

Kryptopterus bicirrhis is a peaceful, highly social species that thrives in schools. Unlike most catfish, they are active midwater swimmers, hovering in coordinated groups with their bodies angled slightly head-up. They remain relatively stationary, gently undulating their anal fins to maintain position. They are most active during the day in well-established, stress-free aquariums with subdued lighting. In bright light or inadequate schools, they become stressed, hide, and lose their ghostly transparency. Their synchronized, hovering schooling behavior is mesmerizing to observe. They are non-aggressive and pose no threat to other tank inhabitants. Their delicate, peaceful nature makes them ideal for calm, planted see-through catfish community setups.

Tank Mates

Ideal tank mates for glass catfish include small peaceful schooling fish such as peaceful rasboras, small tetras, Corydoras catfish, and small loaches. Avoid large predatory fish, aggressive cichlids, fin-nippers, boisterous fast-feeding species, and very large catfish that may intimidate or prey on them. Multiple schools of peaceful fish can coexist well, creating a lively, harmonious community. Shrimp and snails are generally safe. Their shy, delicate nature and slow feeding habits mean they are best suited to calm, dimly lit glass catfish for sale community setups with similarly gentle, non-competitive tankmates that share the same water requirements.

Breeding

Kryptopterus bicirrhis breeding is uncommon in home aquariums, and reliable reports are limited. If it occurs, it likely requires a mature, very clean, soft-water setup with heavy planting and excellent water quality. Eggs and fry would require very fine foods such as infusoria or liquid fry food initially, progressing to newly hatched brine shrimp as they grow. Little detailed information is available on spawning triggers or parental care. Breeding attempts should only be undertaken by experienced aquarists with appropriate facilities, specialized knowledge, and patience. Most aquarium specimens are wild-caught or commercially bred, and home breeding success is rare.

Why Buy from Tropical Fish Co

Tropical Fish Co is your trusted source for healthy, well-acclimatized glass catfish for sale UK, including the mesmerizing Kryptopterus bicirrhis. 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 delicate buy glass catfish online uk. 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 catfish for sale UK online. Whether you're building a peaceful planted tank or seeking a unique, translucent addition to your community setup, our glass catfish deliver both elegance and intrigue.