I found out tannin is something you really don't have to put up with, I once boiled a big piece of M-wood 8 times each time dumping out the tannin until it was almost clear on the 8th boil. Didn't darken my tank one bit, unfortunately it diden't drop my PH either. So I guess if you want driftwood for high PH, better put up with the tannin.
Ill retrieve that stump once I see the fuzz subside. I thought for sure scotching it on the fire would stop this stuff though. Plus it might look kind of cool.