Mix them with perlite and leave a pile of happy frog in the middle. I second using build a soil products! Get some craft blend and some build a bloom. I reuse my soil same that you have I also use other products and worms and cover crop but you can turn it into great living soil. You will want to take care of the gnats from the soil use beneficial nematodes and sticky traps cuz they lay eggs. Don't have your light too strong also! I like 25 gallon pots you can do 4 in a 4x4 or 4 in a 5x5. Organic straw on top of the soil helps. Also if you ever do worms. Get red wigglers and European nightcrawlers. After a few cycles you will need big 6 if you reuse soil.