When i do soil beds, i mix my own mixture. Its wormcastings,high P bat guano,rare earth silicate,OxyCal. I mix it like this for a 4'x8'x10" wood bed. 2 1000 hps over one bed with bat wings.
I buy 3 3.8cubic ft bales of Promix hp. 1 large bag of wormcasting, 1 large rare earth, 2 empty rare...