This is recommended by everyone that knows what they're doing. Have a spare, of *everything*.
Now this, on the other hand, is total bullcrap.
OP has no idea what is *sanitary*, OP is not a microbiologist.
OP should *gently* wash the mask with soap and water, and it will be *sanitary*. replace filters *when they are dirty*, replace the hose and water tank *if they fail*.