The waters (at the exit of Polichnitos towards Vatera) in the hot springs facilities, spring from many places within the earth, through volcanic primary and secondary porous rocks. Free-flowing water that evaporates, staining the bottom red due to growing thermophilic bugs (algae). Their temperature is between 67°C and 92°C (in the baths is between 42°C and 44°C) and they are considered one of the warmest in Europe.
Based on their physicochemical composition, the thermal waters of Polichnitos are classified in the group of chlorinated springs. The water is clear, odorless and enriched with natural radon radiation 15-25Mu, with oxycarbonates, chlorides and sulfates of calcium, sodium with free carbon dioxide, with iron compounds, magnesium, manganese, oxygen and very small amounts of iodine and bromine.