What is the point of using a "detergent"? It won't remove any mineral deposits or rust scale... sounds like snake oil to me.

Draining the radiator and block every three to five years and replacing with a 50/50 blend of Zerex G-05 and distilled water should keep your cooling system squeaky clean. The G-05 has surfactants that reduce surface tension so you don't need "soap", Water Wetter, or any other snake oil for proper cooling system performance.

If you buy an old model that appears to have not been maintained properly and has evidence of loose debris in the cooling system, do a thorough backflush with tap water until the debris is flushed out.

Duke