A modular array of containers placed in parallel for electrolytic solutions used in metals electrolysis processes, particularly for metals electrowinning and electrorefining processes, assemblable from joinable and sealable prefabricated panels with other equal or similar ones, comprising at least a pair of opposite end walls (1, 2), lateral walls (3, 4), a plurality of floor panels (5) and a plurality of intermediate transverse walls (6), the modular array of containers having a common wall between two adjacent containers, the common wall defined by said intermediate transverse walls (6). At least the intermediate walls (6) of the array of containers comprise each one a passage (7, 8) integrated to the wall for the protected feeding and distribution of the loaded electrolytic solution; these walls also being of a reduced wall width in the middle with respect to at least one of its ends and its upper and lower part; said at least one end and upper and lower part of the walls defined by edge formations (9, 10, 11, 12) in which at least one of the formations contains said passage within.