hello everyone. ok, i have the tf 100 test kit, when i test my cya i hold the tube waist level and i fill till i can't see the black dot, i look at the level of the water and get my reading. i hold it back down to my waist and i can see the black dot again, so i fill it some more till it disappears again and check the reading, when i put it back waist level, i see the dot again, its less visible then the first time, then i add more. by the third time the dot disappears for good. my question is what's my reading the first one or when the dot is gone for good?