PURPOSE: To prevent water from leaking even if there is a certain depth of the water and enable the perforation of holes for filtering water by joining a glass plate through magnets to an acrylic resin plate.

CONSTITUTION: The objective live fish tank is composed of a cylindrical tank body 8 formed by mutually joining a glass plate 1 to an acrylic resin plate 2, an upper frame 9 engaged along the top edge of the cylindrical tank body 8 and a bottom plate part 10 engaged with the lower end of the cylindrical tank body 8. Both the right and left end faces of the glass plate 1 and the acrylic resin plate 2 are joined by mutually attracting magnets 5 and 7 in which the peripheries are kept in a watertight state with a silicone adhesive, etc. The bottom plate part 10 and the cylindrical tank body 8 are joined by engaging the lower end of the cylindrical tank body 8 with an engaging groove 12 formed in the bottom plate part 10.