the EM is a great idea, glad to hear you are using that.
for recycling your soil you need something cheap and affective - worms. worms are mother natures soil recycling and renewing machines. they are like the intestinal track for the earth. as the soil and other matter go through the worms bellies it get renewed. also the healthy bacteria (like EM) LOVE worms castings, they really do.
here are some articles on worm soil recycling, also known as vermicomposting. you can make your own vermicomposting bin.
here are instructions to make your own bin. these people are using pure food scraps so it would take longer for the worms to totally break the food down into castings than it would to just recycle the soil you have.