I bought two nice small pieces of Driftwood a few weeks ago and boiled them for hours. Boiled on half then the other then left them in water a couple of days and they sank right in my tank with no darkness. Today I bought a larger piece but I don't think my pot will even go half and half because it's much longer. The middle will never get boiled. Can I just boil both ends then leave it in water for a longer period of time? My last two didn't have any tannins and sank right down. How long would it have to sit to get all the tannins out?