Yep. As I stated, a faint line is a negative.

When testing yourself, always use the first void of the day when THCA concentrations would normally be at their highest and had not been affected by any fluid consumption (which would skew the test result) occuring during the course of the day.

If youre consistently testing negative with the first void of the day (again faint or bold line) then youre good to go. No need for any dilution or substitution. Just drink only enough fluids to where youre able to produce a sufficient amount of urine sample at the collection facility on the day of the U/A.