The invention consists in a disposable module (31) for purifying a fluid, in particular water, adapted to form part of a thud purification system and comprising fluid purification means (25, 28), a housing (35) in which the purification means are housed, and means for removably connecting the purification module (31) to the purification system to establish fluid communication between the purification system and the purification module (31), characterized in that the housing (35) contains from the outset a cleaning agent (36) disposed to come into contact with the fluid caused to circulate inside the housing (35) to clean at least a portion of the purification system, it also consists in the purification system and corresponding fabrication and cleaning methods.