First of all, make sure that you follow each step of the porosity test properly with the cleaning part and making sure your hair doesn't 'sit' on top of the water without breaking the surface. Secondly: Yes, it is possible to have several porosity on your head. 2 main scenario. Either you have low porosity hair and the end turned high porosity due to damage OR you grow hair of different porosity on different areas on your head. A good start to choose your conditioner formulation is to assess if there is more high porosity or low porosity surface on your head and go for the main one. You can also try the recipe for medium porosity and see from there in which direction you should tweak the recipe. Porosity is only one of the many factors that influence which product we should use. We teach the entire unique hair profile and how to customise your entire haircare routine, from all the products you use to how to boost hair growth and reduce hair loss with better lifestyle habits. Stay tuned for Graduation day where there is big news about it! ;-)