I do not reuse soil because of stability and consistancy changes, i use a fox farm mix of light warrior, ocean forest, and fox farm potting soil, combined with big and chunky perlite by fox farm, for flowering additions combine Peace of Mind Flowering Ferts. If you resuse soil, it will not be as potent because the plants have already extracted the nutes from the soil. Also, pests could be lingering w/o you knowing.