For the purpose of development of steel fish reef, a teｓt reef was installed off the shore at Katsuura-cho, Nachi, Wakayama prefecture in 1982. Stability and durability of the structure and swaming effect of the fish reef have been checked with eleven diving works. Specially, for the purpose of researching the steel corrosion amount above the water depth of about 50m, several test pieces were installed, and have been checked for a stated period. The reef has shown the satisfying function and has been in sufficient condition in stability and durability for these eleven years since its installment.
