True loaches are mostly scavengers and are omnivorous, usually not very picky about their food. They may eat aquatic crustaceans, insects, and other small invertebrates, as well as scraps of organic detritus. Many live in eutrophic waters of generally poor quality and feed on tubifex worms and similar benthos associated with such habitat. Some of these loaches have adapted to low oxygen levels in warm, muddy rivers or dirty ponds by being able to gulp up atmospheric oxygen. Some species, particularly from the genera "Cobitis" and especially "Misgurnus", are sensitive to changing air pressure. They change their behavior accordingly, and as these changes in activity are usually followed by a change in weather, they are commonly known as "weather fishes" or "weather loaches".