Some participants accept that fish are very effective at controlling larvae, so fish are kept in non-potable water containers, e.g., containers for water plants such as lotus. Some larvivorous fish are colorful and beautiful so people rear them, mainly in water plant containers, as recreation. As mentioned in health education materials, fish should be kept in water containers that cannot be covered by lids, but fish are difficult to maintain. Health education information does not include details about maintaining fish. Moreover, several people thought that fish dirtied the water or brought disease, and hence were not a desirable option.