Abstract: An inexpensive, liquid-supplying and liquid-cleaning apparatus capable of functioning through capillary action. Such apparatus finds use in humidification systems, or life-support systems of varying types. It is characterized by the use of a microporous membrane having pores of a nominal size of less than 10 microns which act as capillaries in the liquid supply means, and also as means to exclude algae, fungi, etc. from the liquid being supplied. The more advantageous embodiments of the apparatus comprise a novel vacuum/pressure seal to help avoid leakage of water conducted from a flexible hose into a rigid container.