okay here is the deal with water so please pay close attention because i am sick and tired of repeating myself on this subject
1. bottled water: most of them are just tap water in plastic. you can test them out with a pool kit to see chlorine content. aquafina and dasani are the absolute worst (owned by coke/pepsi). Fiji water is the best
2. tap water: full of shit you don't want in your body. if you live in the USA some parts of the country are so bad that you can die from drinking it (see Flint, MI) .. other parts it will slowly kill you cause it is full of bad shit
3. filtered tap water: sounds great right but pay attention, you are filtering out EVERYTHING good and bad. the good being minerals that WE NEED. so you are ending up with just plain water. you cannot hydrate properly with plain water especially after a lot of sweating.
4. ionized water: instead of filtering out EVERYTHING good and bad. it separates the good and bad. spits out the bad into your sink and you can drink the good.
hope this helps you understand the differences.