It may be worth noting that if your water is only chlorinated with chlorine (and not chloramine, which is quite common now as well), leaving it in the fridge ov

It may be worth noting that if your water is only chlorinated with chlorine (and not chloramine, which is quite common now as well), leaving it in the fridge overnight can allow some of the chlorine to evaporate, making your water taste better even without a filter. In this case he allowed both his tap water and filtered water to cool overnight, which would tend to understate the taste difference between freshly pulled tap water and freshly filtered water (if that filter effectively removes chlorine).