Why does it matter if she is a professional? She is simply asking a question that to my knowledge has a simple answer. I understand some forums are for professionals only, but helping someone out that isn't a professional isn't going to kill you. I am a certified aesthetician/makeup artist and I would never tell someone "I'm not going to give you information because you are not a professional". People not in the industry have the right to use professional products just as you have the right to purchase professional makeup and skin care products. We are not here to educate people on how to use professional products in their hair, no, but it's not like she's asking how to do a shampoo cocktail or how to tone highlights. Stop keeping up the steriotype that hairdressers are jerks. As for your question madame, I use 5/75 in my hair as well and just so happen to use the 0/68 as a nice little violet undertone, it looks fantastic.