What is the difference between carbon block and KDF filters?
Carbon block has come a long way as far as performance and we have many very good block filters available. The biggest factor why we still recommend KDF is because KDF is classified as a bacteriostatic device. Dark, warm and wet environments are a perfect place for bacteria, mold and algae to grow and will almost certainly grow inside a carbon block. This is because there are currently only 2 ways to create an environment within a filter in which bacteria growth is restricted-by using carbon impregnated with silver or by using KDF. Few, if any carbon block companies use silver because it is itself a toxic contaminant and KDF cannot be utilized in a carbon block. Therefore, carbon block is a perfect environment for algae and bacteria growth, while a KDF filter has a “bacteriostatic” environment where growth is restricted.
