<；P>；PROBLEM TO BE SOLVED: To provide a method can cultivate floating larvae of the general bivalves at a high density and high efficiency by removing residues such as excrements, dead shells and remaining baits on the bottom of a water tank without mixing them with the floating larvae in cultivation, and perform washing of the cultivation water tank and a filter without limited in human labor time. <；P>；SOLUTION: Plural cultivation water tanks having cultivation water pooled therein are provided to allow the selective use of cultivation water tanks A and B, and bivalve larvae are cultivated in one cultivation water tank A for a predetermined period of time. The cultivation water in one cultivation water tank is increased from that of the start of the cultivation； the floating larvae are transferred into the other cultivation water tank B together with the thus increased cultivation water via a larvae-transporting pathway, and the thus transported floating larvae are cultivated in the other cultivation water tank. After the preceding transportation, the inside of the former one cultivation water tank is washed with washing means 7 and 15. These operation steps are automatically conducted after the passage of a predetermined time lapse. <；P>；COPYRIGHT: (C)2009,JPO&INPIT
