The “wood” that is sold in pet shops for the use in normal aquaria belongs to totally different sorts of wood. Wood from peat regions is the best, but it is normally sold dried out and that is bad already. If you are once able to get hold of f r e s h wet wood pieces from bogs or swamps, take it. It’s just the best. If you only get hold of dried pieces, you must soak it before some days in destilled or at least pure rain water and continue to measure pH and conductivity.
There are many sort of “oak-wood” sold, too, and it is impossible to tell generally it to be goood or bad. You must try. And I don’t remember the place, but I warned to use Mopani-wood some time ago. This African wood is entirely useless resp. wrong for use in blackwater tanks with a stabile low pH.
A good alternative to fresh bog wood from peat regions is alder from creeks or small rivers, but only dead pieces that could be collected under water.
Therefore mind: Wood is not the same as wood. And pet shops sell many things that are entirely useless for Paro-lovers.