For years I went with 100 deg F. Shock getting in but I got used to it and sometimes even went to 101 - 102. Somehow in my old age I can't take any more than ~95 now or else I'll actually break into a sweat. 105 is a recipe for disaster. 105 + drunken old people = tragic boiled death. In the summer I just turn off the heater and it sits at about 75 for a quick refreshing dip.