White tongue as everyone refers to in the case of oral candida(oral thrush) is a very thick white coating over an irritated red tongue that is almost painful to get rid of...it stays there all day unless you treat it!
Normally,After a night of sleep the tongue accumulates bacterias (as you also do on the teeth because of decreased saliva) which accumulates as a thin white layer and that normally disappears with tooth brushing...
There is a huge difference between the too!
Mouthwashing with Grapefruit-Seed-Extract (grapefruit seed extract) is a good way to get rid of oral candida if you still think that is what you have. Mouthwashing with Nystatin is one of the usual prescribed medication.
As a note: you have to be very immunosupressed(read: very sick) with candida albican to get real oral thrush...and trust me it hurts...you can't scrape it out of your tongue because it is too painful!