Grey fairy and French fairy are native to the tropical waters of the Atlantic Ocean. In addition, gray immortals sometimes appear in New England as far north as the United States. The colors of these two varieties are much worse than those produced in the Pacific Ocean and Indian Ocean. Faxian and Grey Fairy need cooler temperatures, so the water temperature in the aquarium should be kept within 2 1~24℃ as far as possible. The same is true of immortals and butterflies in the yellow circle. If the temperature is limited, they will live better.