Quote Originally Posted by MikeM View Post
Hikkui is quite a mystery in itself. It is associated with sun exposure, genetic pre-disposition, high nitrate levels, but none of these factors seem to explain every instance. Why a period in greenwater temporarily resolves it, while keeping in well-shaded conditions does not seem to help established cases (but may reduce new occurrences???), has not been explained satisfactorily by anyone. I can make various guesses, but none hold up 100%. No doubt the effectiveness of greenwater algae in blocking light and consuming ammonia is at the root of the 'cures'.
Green algae also has lots of beta carotine and produces abundant oxygen, two good factors that contribute to good skin. Some research even suggest its also a cancer treatment.