Been a while since I have been around but I have been growing the whole time and wanted to let whomever it was that asked about recycling soil.. My current soil is roughly 4yrs old, grown dozens and dozens of plants and all I do is reamend after each grow and let that bin cook while I use an already cooked bin of soil for the next grow, and so on.. I have 4 large totes that I write the dates on and sometimes I will write how much KIS or meals I added to see if it changes and right before planting, I add either some more perlite or coco fiber for aeration..
Also, found a new microbe product that I am running side by side with Recharge to see if there is a difference in terpenes and frost.. It's called "Soil Balance".. A little goes a LOOOOONG way.. 1/16th of a tsp per gallon or .1-.5g..