I just bought a water purifier for a hike thats coming up and I just ran some water threw it for the first time and at first the water came out black and then it was clear, I ran alot of hot water threw it and filled up a glass and the water looked clear but when I looked in the glass I saw little black flakes floating around. is this normal or what. also theres black streaks in the rubber hose that carries water from filter to the canteen. Is there something I need to do to break it in or clean it up/out before I use it.......