I you plant to get wood for pleco to rasp on, Make sure its not mopani wood, Bog wood is best as mopani is to hard for it to rasp
this is interesting, do you have any links to this problem? i have come across people saying mopani is a bit hard, though only in places, for plecos, but i have not found any comments that is is truly bad for them. pleases do not think i am saying this is not so. its just the first time i have come across this, and for the benefit of my fish, would like to look into it.