The small amount of salt wood will pick up from the ocean is not a problem. People actually use salt in medicines or add it to the tank. It is assumed you will be treating it and part of that will be to rinse it.
There are other things which it may have riding along like oil from the water. Those can be bad even in small amounts. An easy way to clean things is a bleach water soak. Bleach has the advantage of soaking into all the little spots as you let it soak at least overnight. It kills almost all vermin like snails and their eggs, worms and fungus and reacts to neutralize almost all chemicals. The type of wood is not really too important as there will be little to no sap left if it is truly dry wood.
Once the wood soaks good, take it out and treat it just like you might your clothing. Rinsing will remove and dilute the bleach and drying will let the rest of the chlorine blow away.
Any time some major item is added to the tank, some extra care is called for to watch for any changes. Depending on your water, the PH may shift. The wood may color the water if not totally dry but not having bark makes it sound ready to be used. Wood with bark left is often not dry enough.
Simple,easy and done all the time. GO for it!