The invention provides a humidifier apparatus (100) comprising (i) a first chamber (110) for containing water (101), (ii) a humidifying element (120) configured to facilitate evaporation and/or nebulization of water (101) contained in the first chamber (110), wherein the humidifying element (120) comprises a wick element (130), (iii) a replaceable or refillable unit (230) for containing an immobilized phosphate removing material (150), wherein the phosphate removing material (150) is configured to reduce a concentration of phosphate in water (101) before evaporation and/or nebulization of the water (101), and wherein the wick element (130) comprises the phosphate removing material (150), wherein the phosphate removing material (150) is comprised by the wick element (130) as one or more of impregnated phosphate removing material (150) and coated phosphate removing material (150), and wherein the wick element (130) is configured as the replaceable unit (230). Further, a wick element (130) comprising a phosphate removing material (150) is presented.
