ST. TROPICA SHAMPOO STUDY
Background: On very rare occasions (<1%), we learned some customers found that our Coconut Oil based Hair Mask did not properly wash out of their hair – resulting in a less-than-great experience (i.e. leaving hair in a greasy mess!)
Objective: Baffled at how the vast majority of customers around the world, have had a fabulous Hair Mask experience, we decided to investigate. We thought about hair types, water hardness/softness, seasonality/climate, diet, hydration, and of course: shampoo.  After much thought, research, and process of elimination, we had reason to believe that shampoo might be the culprit.
Methodology: Direct testing of multiple shampoo brands, on our own team, with different hair types, used as part of our own ST. TROPICA Hair Mask directions (used to wash out our own Hair Mask treatment; shampooing twice as directed).
Results: We found that every single Conventional shampoo on the market we tested, including baby shampoo, effectively washed out our coconut oil based hair mask.  We also found that almost all Natural/Organic shampoos we tested also effectively washed out our coconut oil based hair mask. Our findings to date indicate that only a tiny segment of natural/organic shampoos could not effectively (easily) wash out our coconut oil based hair mask.  See a detailed list below.
Explanation/Logic: We believe the reason for the tiny segment of Natural/Organic shampoos’ inability to wash out our coconut oil hair mask is because those shampoos simply have less cleansing ability; as a result of containing significantly less actual cleansers (cleansing agents aka surfactants).
A Work in Progress: We will continue to test, and grow this list!  If you can contribute to the list, please let us know.  We will still test on ourselves to confirm your results.
*   Effectively washes out coconut oil from hair (shampooing twice as directed) as tested by us.
** Does not wash out coconut oil from hair (shampooing twice as directed) also as tested by us.  (Left our hair a greasy mess)