Need hockey rink ice making suggestions, can you help me out?

Trouble making good quality ice in my ice rink. 1st problem is that we use well water. 2nd is the building has no insulation. I am laying down 160 degrees water and surface temperature of the ice is between 20 and 24 degrees. Is it better to keep the brine return temperature to 16 degrees all day or should I ice temper it. Ice is soft and chippy... Any suggestions would be great.. I want good quality control for competitive hockey games at the school I work at. Thanks in advance.