A large amount of cotton is found in lakes, rivers, haor-baor, canal-bil, ponds etc. in Bangladesh, India and Myanmar. They live in the middle layer of water. Roe fish does not survive below 14 degrees Celsius. The best temperature for its growth is 30-32 degrees Celsius.
Ruhi fish are omnivores. Caterpillars feed on zooplankton and Angulipona feed on phytoplankton. Adult fish feed on algae and soft plants. The food of commercially cultivated cotton fish is rice bran, wheat husk, mustard husk, other supplementary food etc.