beech chips are not the best substrate for leo...they lick the ground sometimes and are not the best/most accurate shot when hunting and my ingest some which would cause major health issues, that is also the reason why sand is not recommend either...
Oh the guy in the Reptile shop told me Beech Chips are fine for it. the only snad he recommended is coral sand like ya use in fish tanks, coz other sands can cause impaction, where coral sand doesnt