Honestly, I've done both. I drank tap water a lot and I've had bottles of water a lot. So in my opinion, the best medium is filtered water and it saves you a lot of money as well from just buying bottled water over and over because that's just going to get expensive at one point. But yeah, tap water, if you get used to it, it's not as bad as people make out to be but the first time you try is it is quite bad.