PROBLEM TO BE SOLVED: To provide a block for a fish bank fixable easily by algae, suitable for inhabitation/egg production/incubation of an aquatic animal, and doing little damage to an environment of an installation water area.SOLUTION: In a block 10 for a fish bank, since a full length, or a dimension of a width of a formed hole, an open hole 20, a tapered hole, or openings 22, 24 of a slice groove, is suitable for inhabitation/egg production/incubation of an aquatic animal, aquatic animals gathers easily. Further, since a natural stone 12 is used, microbes or algae easily adhere or fix thereto, and a harmful matter is hardly eluted therefrom, and a flow velocity of water flow near the block for the fish bank is hardly affected thereby.SELECTED DRAWING: Figure 1【課題】藻類が固着し易く、水生動物の生息・産卵・孵化に適しており、設置した水域の環境に対する被害が少ない漁礁用ブロックを提供すること。【解決手段】漁礁用ブロック１０は、形成されている穴、貫通孔２０、先細穴、又はスライス溝の開口部２２，２４，全長、又は幅の寸法が、水生動物の生息・産卵・孵化に適しているので、水生動物が集まり易い。また、自然石１２を用いているため、粗い表面に微生物や藻類が付着又は固着し易く、有害物質が溶出する可能性が低く、漁礁用ブロックの周辺の水流の流速に影響を与え難い。【選択図】図１
