If you have any concerns about the drift wood, depending upon where you got it. If it is a found piece of wood: put it in a 250 degree over for about an hour or more depending upon size, this low heat will kill off any unwanted things that might still be in the wood (such as spores) and not harm the wood itself. As with anytime one uses an oven, do not leave unattended. Otherwise, if it came from a pet store/rept show: RO (reverse osmosis) water is a purification process which removes certain chemicals and adds certain other chemicals, it is mostly used for saltwater or discus fishkeeping. Some lfs also sell it by the gallon. You can also use distilled water to make sure that you are not adding any unwated chemicals. I would always rinse any new decor that I place in any tank, at the very least to remove any dust. Then I let it dry completely (or place in over, then let it cool down, then a quick rinse) before placing in my vivariums or fish tanks, just to be on the safe side.