I've have a piece of wood in my tank for about a year and it still puts a yellowish tint in the water. Boiling it can help tannins release faster but it will also soften the wood and break down faster in your tank. I put mine in a bucket water for a week with multiple water changes. With the last few changes I added some Prime to it.I've recently got a piece of blackwood at lfs. I'm boiling it. Will water ever not get stained brown while boiling? I changed water a few times in 8 hour period.