All depends if you want any tannins in the tank water, some fish perfer tannins in the water (south american fish mostly), as for soaking it. Take the bogwood and wash it under tap water this will wash any chemicals that may be on it off, then fill a bucket up with water and place the wood in the bucket, check then bucket the next day, the water should be brown, empty the bucket and repeat the process until ever the bogwood has stoped leaching tannins or untill you ae happy with the colour of the water. this can take weeks to complete. Alternately you can boil the bogwood in water for between 1-2 hours is a quick alternative to letting it sit soaking in water for weeks. But this is a very smelly and dirty process for most home aquarists. It also destroys any beneficial fungus or bacteria there may have been on it. If the bogwood is already pretreated it should sink rapidly within a day and will not leak out high levels of tannins. Once you're happy with the way the wood is looking, you should add it to your aquarium.
