Every piece in there... I put in a large cooler and filled the cooler with boiling water. IT would be BLACK in about an hour or so. I would let it sit in that water until the next day and then do it again. I did that 4-5 days with each piece of drift wood.
Even with doing that... for months afterwards after a week, my water would be significantly tea colored. After the weekly water change, it would be good... but then a week later... tea colored.
I was REAL close to taking it out. Now, 5 months later... at each weeks water changes, you can barely see the tea color. I would say another month and it should be completely gone.
No clue how long it would have taken if I hadnt boiled it day after day after day.