Of course chlorine will kill the micro field, but with all the humics, fulvics, organic acids, unbonded calcium in nectar, it becomes way less of a microbe killer and ties chlorine up. I would never just plain water with chlorine treated water. Hell phosphoric acid will kill microbes too but life grows freely inside the Hades down bottle. Its all about the concentrations of chlorine salts or phosphoric acids in solution whether it will kill of microbes. You don't need to baby your microbes, they are hardy creatures that deal with all kinds of hurdles to sustain life in their environment. My cheap high school microscope proved a lot of my opinions here for what's in my water source. Its one of the reasons I dropped RO for charcoal/KDF and havnt looked back.