I have recently become interested in building my own home-brew water filtration unit; during my online research on the subject, I came across active carbon (aka activated charcoal). It seems like it may be a great addition to my current ideas, although I have a few questions:
1: Where can I get active carbon that is okay for human consumption? (It's not like I will be taking it in directly, although drinking water will pass directly through it).
2: How can I effectively use the active carbon, and also use it efficiently?
3: What is the filtering lifespan of active carbon? (How long can it effectively clean water? For a given amount of carbon, and water).
Thank you in advance :)