I understand alkaline water. But the benefits of MMS will surpase that of alkaline water at least for the short term if you really have pathogen problems. Get rid of the pathogens then return to alkaline water to maintain a ph alkaline environment. I think a test is called for because if you are negating the MMS then you are just wasting your time.
I have used mms with a variety of juices and noticed that the mms did not work if I drank them, particulary grape, even if it has no added vitamin c.
MMS requires an acid solution to work best. Only a test will tell you for sure.