PH TESTING TAPE Monitor your acidity and alkalinity. pH Testing Tape is an easy and non-invasive visual aid to determine the pH of your saliva and urine, which, to a degree, reflect the state of your bloodstream. Test each morning and again two hours after eating to see how the foods and beverages you consume affect your pH balance. 15 ft. Be sure not to touch area of tape you will test your sample with. Anything that touches the tape will influence results.