im sure that would work because the styro balls are just heated and stuck together without using any kind of glue. i seen that stuff used in cheap growing mediums but you should stick to perlite. cause it holds a lot more moisture and air pockets and not made with chems. just buy a bag! its really cheap and you dont have to mess around with trying to break that stuff up and having it stick to everything that has static on it! dont use styro, break down and buy perlite. it will save you headaches in the long run.