Best shampoo to use for color treated hair that doesn't leave buildup?

Okay, so here is the deal. I color my hair red. My hair dresser recommended the Pureology Antifade shampoo (pink bottle) and conditioner and I took her advice. It leaves my hair feeling "waxy." I find this is true with a lot of shampoos and have always alternated every few washes. So, I tried it using my previous favorite, Paul Mitchell Lavender Mint Moisturizing Shampoo & Conditioner. Still feels waxy and looks a bit greasy. I would like to find something that conserves color, doesn't leave buildup and I'd like to stay earth friendly/organic if possible. Any suggestions? Thanks!