It has been shown that the levels of pH do not affect health, all health benefits are found in hydrogen water. However, some people still prefer to drink acidic and alkaline water from our Echo 7,9, and 9 Ultra machines. If you chose to, we don’t recommend drinking over a level 2 on the acid and alkaline water settings. Be careful that you’re not consuming water higher than a 10pH as that can cause issues. If your water is higher than 10pH you can also add a few lemon juice drops to lower the pH level. You can safely mix all 4 levels equally in a glass to get more hydrogen.