Hey guys I've got 5x5 flower with a 960 cfm fan and a 8in carbon scrubber it's way over powered for my size! But my question is how often do you change it out? I don't smell anything but I smoke so dam much I didn't smell anything to begin with! And my house always smells like bud! I've had my current scrubber for about 18 months give or take a few!