I am looking to make a cheap bulk substrate that I can use maybe both inside and outside.
I can get my hands on cheap wood-chips(6 pounds/1 dollar) and popcorn for wild-boar(4 pounds/1 dollar). I pay zero for gypsum. Is this a possible mix and should I add something else? Maybe some brownrice flour? What would be the optimal ratio of each substance?
Also, what is the main difference between spawn- and bulk-substrate? I experienced perfect results with my spawn-substrate(vermiculite and brownrice flour), not so good with bulk-substrate(Vermiculite, Perlite and gypsum. Why? Was the bulk-substrate maybe missing the brownrice flour?
Thanks.