Theres 2 aveda shampoo's im interested it. The Black Malva, and the Colour Conserve. It says Black Malva diminishes red or brassy tones. And i got some of that. So pretty much my hair will seem les red? And the colour conserve apparently prevents colour from fading. So i plan on dying my hair with the non-permanent colour to deep brown once every 6 - 8 weeks till my roots have grown a significant amount. How much longer will the colour conserve keep my hair deep brown? Answers would be greatly appreciated since im really really stressed out over my hair.