The blue is very intense. I have it diluted - ie equal added to the incoming bathwater.
The water was deep-blue even at a small amount. It looked really pretty.
However, it will not stain also quite strong. The tub has gotten nothing through the dilution and subsequent rinsing. But a small drop on my hand - and the fingers then remained blue first! Then I had the bottle completely wipe off, so that nothing drips blue on. This is obviously a somewhat unpleasant struggle.
I recommend instead try other times (less coloring) Kneipp baths.
