Yes, Voodoo combined w/ Pirahna and Tarantula will increase your root mass, giving you a heartier, healthier plant that's more resistant to pests and other problems. I can't recall whether Voodoo is the bacteria or the fungal spores or what, but using all three I notice a HUGE ungodly change in my plants, and they seem pretty healthy too. I use Pirahna and Tarantula in my weekly mix, but I only use Voodoo every other week due to it's price. All three components compliment each other and work great, I won't do another crop without them.