What if the developer solution does not saturate the white disc in the sampling port after the reading window fills?
Gently tap the corner of the monitor closest to the sampling port onto the palm of your hand (as seen in the second box of the “1. Activate Monitor” section of the Instructions). The disc must be fully saturated with developer solutions so that the solution will not flow out of the reading window when the monitor is placed flat on the table for the 4-minute development period.