water wetter

my car dont heat at all it stays at 180 or under but i thought that if it cooled down some it was a help just dont want to spend 10.00 on however many bottles and not see any diff... so i think that im good with just the alum. radi and the stuff on it now....i went to the water pump drive and electric fan and drove the car around sat. about 10 miles i think and never got pass 180 then so i think ill be okay......