PURPOSE: To easily regenerate a pisciculture pond in a short time by taking fishes out of a pisciculture pond containing deposited sludge, draining the water and placing foamed concrete hardened to an extent not to sink into the sludge, thereby forming a new bottom face of the pond.

CONSTITUTION: Fishes are taken out of a pisciculture pond containing deposited sludge and water is drained from the pond. Foamed concrete having a specific gravity of slightly higher than 1.0 and hardened to an extent not to sink into the sludge is placed on the sludge layer at a thickness of from several tens mm to one hundred odd mm to form a new bottom face and obtain a regenerated pisciculture pond.