Pure Water Products, LLC (PWP) products

White filters cost less than clear, not because they`re inferior but because it costs more to make a clear filter housing. White housings have the advantage of not allowing algae to grow, as sometimes happens with clear. (Algae need light.)

Double filters have twice the filtration capacity and the advantage of multi-purpose use. For example, placing a sediment cartridge in the first canister will protect the more expensive carbon block cartridge in the second canister from premature blockage from sediment. Double filters are especially valuable if you`re removing chloramine, which requires longer contact time for removal. Two softening cartridges last twice as long as one.