When we visited Masaaki Kawamura's pond in Nagano Prefecture, his koi friend Toshiro Ichikawa welcomed us just by the pond. Ichikawa-san studied the fishery pond system at a university, and now employing his knowledge in water and soil improvement business at a construction company. He designed the pond for Kawamura, and so to speak, he is a koi and water adviser for Kawamura and members in Nagono. The pond system has two unique points. One is that bottom water is taken out through some drain holes of the three pipes equipped on the pond bottom to run into the filtration tank. The other is that water coming after the two mat filter areas is pumped in the center of the filtration tank and sent to the cascades. The wide two-stepped cascades can be sufficiently aerated. By the device that makes circulated water contain as much as air, it is possible to keep no less thaii 50 fish in the 35-ton pond.
展开▼
