A white tongue does not automatically mean thrush. :) It can just be toxins in the main, and perhaps a bit of candida IF you were eating things that feed candida like dairy and sugar. Thrush appears very different from toxins in that it covers the whole entire tongue, it stings, and will also cover the inside of the mouth. The spit test comes back VERY positive when you have thrush.
Cleansing the colon with oxygen will stir things up, and if they don't get OUT they reveal themselves on your tongue so you know you have to flush the colon. So a high colonic, or enema, or lots of fiber and heating, pungent, carminitive herbs while avoiding sweet foods is really all you need to do. If transit times are slow, take a mild laxative like Triphala and fennel tea.