anyone tried using petrified wood
 

Hello I am going hydro and found expenses that I didn't know existed WOW. So my question is has anyone ever tried using petrified wood broken up into small pieces it is very plentiful here and may be P.H balanced I haven't checked not that far along yet but Im getting there one dollar at a time.......Your friendly Uncle Al.

The more porous a medium is the better because it needs to hold oxygen between waterings. Just about any inert material will work. Just some better than others because of the oxygen and other factors.
Give it a try and let us know if it works.