I reuse mine, working out real nice. I try and get as much root out of the coco, its about impossible to get them all out, my girls are doing great too.
I was told can use it up to 3 times and recommended to run a double dose of canazyme through it between plantings to help break down left over roots...
soak it with the zyme maybe 24 hours.......u cant re use it if u use phospho load or hg shooting powder they bind to it and will screw things up.......otherwise like the man said above u can use it 3 or 4 times.......