I just took some photos of the tyndall with a laser pen in the dark of several liquids. One thing I noticed that was the tyndall of tap water was not actually that bright. It was pretty dim in fact. The tyndall of a roughly 10ppm CS that went a little wrong was MUCH stronger. This CS was still mostly clear but was just borderline starting to turn yellowish. I always assumed tap water would have strong tyndall. I took all the photos in mason jars.
~David
