None of them use chlorine or any detergents and only a constant flow of warm water from the hot spring. 
A restaurant seating 70 people will also open at the site focusing on local farm ingredients.  noncleared-maintext”>
 A new natural pool for bathing in will be opening next to Deildartunguhver hot spring in Reykholtsdalur, West Iceland at the end of October. Around 50 to 60 thousand visitors are expected to visit the nature pool annually. 
The pool has been named Krauma and also offers five hot tubs.