How hard are they to keep?
We would class Gastromyzon viriosus as a moderate care level fish. They require a mature aquarium with excellent water quality, strong water flow and high oxygen levels, making them best suited to aquarists who can provide a specialist hillstream setup.
What is its maximum size?
They can grow to around 5–5.5cm in length.
How many can I keep?
They are best kept in a small group, ideally five or more, in a suitably sized aquarium with plenty of rocks and grazing surfaces. Ensure there is enough space for each fish to feed and establish its own resting areas.
What do you feed them?
Gastromyzon viriosus is an excellent algae and biofilm grazer. They spend much of their time grazing on rocks, glass and other surfaces. In addition to natural algae growth, supplement their diet with algae wafers, spirulina-based foods and blanched vegetables. They may also accept small amounts of frozen foods, but their diet should primarily consist of plant-based foods and biofilm. A mature aquarium with plenty of established grazing surfaces is essential, as they can struggle to find enough food in a newly set-up or overly clean tank.
How compatible are they with other fish?
They are peaceful fish that can be kept with other small, non-aggressive species that enjoy similar cool, fast-flowing and oxygen-rich water conditions. Avoid aggressive tank mates and fish that prefer warmer, slower-moving water. Provide plenty of smooth rocks and open grazing areas to help minimise competition for food.