[PeteSB75]

I get new hose/mask/filters every three months, when the DME supplier calls me to ask if I need it. I use only distilled water, but I don't dump the existing water every night - bit of a waste IMO. I clean the mask and tank about once a week. I will use tap water when I am traveling, but it tends to build up mineral deposits on the sides and bottom of the tank pretty quickly, so I always use distilled at home - I keep it around anyway for Cigar Oasis refills.