Cooling System Additive

For the record -- I plan to run tap water and some type of additive - Water Wetter, Purple Ice, Lucas Super Cool -- OR -- ?? (TBD), during the summer months, because it works for me. - Yes I probably should spend more $$, and find the real root of the problem. -- In the cold season, I will use 50% water and 50% anti freeze. -- Thanks to all for the input - several good ideas were presented, and that's the real value of this Forum.