Ive heard of some really excellent results from using teas (recommended for use in soil not hydro), you can buy them pre brewed at most hydro shops but its actually really easy to do your self, all you need is a bucket or tote, a air pump and a bubble stone, there are many things you can use to make the tea but typically you would use things like worm castings, bat/bird guano, soluble kelp, sea weed extract etc, you just fill your bucket/tote with clean, CHLORINE FREE (very important as the chlorine will kill the microbes your trying to colonize) water (RO preferably) add your poop and goodies and let it bubble/brew for 48-72hrs, then just use in place of a watering every 1-3 weeks depending on your soil/situation. The whole point of tea is to feed the microbes in the soil which in turn feed the plants, the healthier the microbes the healthier the plants.
