ʻAʻohe mea ʻawaʻawa, kūʻē i ka wā, kū i ke kemika, kūpaʻa, haʻahaʻa ka wai absorption, kū i nā ʻakika nāwaliwali a me nā mea hoʻoheheʻe organik. ʻO ke aniani kiʻekiʻe, hiki ke pale i ke kukui ultraviolet, nani maikaʻi.