Just read the article myself. I've had a piece of wood I cut from a tree in my parents back yard. It was living (obviously), and I let it sit outside for about a month. Then I used a knife to whittle the outer bark off (it was still green under), and let it sit another month in my basement near the furnace to dry. Then I began the bucket soaking. I just used normal hot tap water, weighed it down with a ceramic pot I used to have in the tank, and would change the water every 2-3 days or so. I've done about 5 changes now and still am getting tannins.
I have not used salt, but might shortly just for the heck of it. I don't really see the need to prevent anything growing on it since it will be treated when finished leeching.
I disagree with using bleach at any point. Hydrogen peroxide will give you identical results without any possible residue needing to be washed off. It's cheap too.
What I plan on doing once the tannins are no longer present is to boil the piece for an hour or so, change the water, try to get the rest of the bark off, if not let it soak more, otherwise, let it sit overnight in a bucket with a bottle of peroxide. This will ensure that anything living on/in the wood is dead (the boiling should have taken care of this though). Then I'll add it to the tank.
