Glass Catfish

The glass catfish has an elongated and tall body, with an unusually long anal fin that extends from the head to the very tail. Its main distinguishing feature is its transparent body, through which the spine and ribs are clearly visible. Near the mouth on its head are two sensitive, long, antenna-like barbels.

Its natural habitat is in the river systems of Southeast Asia, primarily in modern-day Thailand. Specifically, these fish are found in rivers that flow into the Gulf of Thailand. Due to potential confusion within the species, a precise definition of its habitat range requires further research. The catfish prefers to live in still or slow-moving waters, which are often quite murky.

These catfish thrive best in a shoal of at least 6 individuals. Their behavior is calm and peaceful, one might even say modest. It is advisable to avoid cohabitation with active or aggressive species, as well as those significantly larger than them. Other peaceful and small fish typical of Southeast Asia get along wonderfully with glass catfish.

A group of several fish will feel comfortable in an aquarium of 100 liters or more. The decor should include many rooted and floating plants; the latter create additional shading, which is beneficial for these fish. The choice of substrate depends on the needs of the plants and is not critical for the catfish, as they prefer to stay in the middle or upper water layers. Water parameters should be as close as possible to their natural habitat, meaning the water should be soft (in terms of dGH) and slightly acidic (pH). Adding a few dry fallen leaves can give the water a characteristic “tea” tint due to the release of tannins, mimicking the conditions of slow-flowing swamps or marshy river sections in the tropics. More detailed information on dH and pH parameters can be found in the “Hydrochemical Composition of Water” section. The minimum equipment set includes a heater, an aerator, a filter (preferably one that does not create a strong current), and a lighting system set for subdued light. Aquarium care for glass catfish includes daily feeding, regular cleaning of the substrate from organic waste (food remnants, excrement), and weekly water changes of 15–20%. The frequency of changes depends on the number of inhabitants and the efficiency of the filtration system.

In their natural habitat, the glass catfish acts as a small predator, whose diet consists of zooplankton and various invertebrates. If kept in a home aquarium, the fish will happily consume all types of dry foods, be it flakes or pellets. These should be supplemented with live or frozen meaty foods, such as bloodworms, daphnia, grindal worms, and brine shrimp. It is important to ensure a varied diet! Feeding is recommended 2–3 times a day, offering an amount of food that the fish can consume within 5 minutes.

No cases of successful breeding of glass catfish in home aquarium conditions have been recorded; at least, the author has not found such information. These fish are supplied to retail and wholesale networks by breeders from Asia, where they are bred on specialized fish farms organized directly in their natural environment.

Catfish are very sensitive to water quality and composition; any changes in parameters or deterioration of conditions immediately affect their well-being. This increases the fish's susceptibility to infections and can lead to various diseases. In a biologically balanced aquarium with suitable conditions, health problems usually do not arise. More details on symptoms and treatment methods can be found in the “Aquarium Fish Diseases” section.

When purchasing, choose only active individuals that stay in a shoal and show no signs of emaciation. Avoid fish with cloudy eyes, damaged fins, or visible spots on their transparent bodies, as glass catfish are extremely sensitive to transport conditions and stress. At the store, be sure to ask how long the fish have been imported and prefer individuals that have already undergone an adaptation period in the aquarium. Given that the species is often sourced from the wild, it is important to ensure the absence of parasites and signs of bacterial infections that may appear in the first few days after relocation. Remember that quarantine for new individuals is a mandatory condition before introducing them to the main aquarium.