by Michael Pickering
In the process of washing laundry the cleaning agent is the water, the “universal solvent.” The surfactant (soap/detergent) facilitates the removal of strongly adsorbed and hydrophobic soil from the clothes. Foam, however, is a contaminant. Suds stabilizers added to the surfactant create persistent foam. Unfortunately, most consumers believe foaming to be evidence of a good surfactant; that it is desirable. The truth is quite the opposite. Foam residues are difficult to remove. Notice, after all, that the foam is excluded from the solution/emulsion phase: it floats. Thus the rinse cycle is inadequate to the task of removing it. It is the residue of these suds stabilizers on laundered swim suits that necessitate the frequent exchanging of spa water. Contaminated hot tubs, when set to the ‘jets’ cycle, quickly build up foam on the surface of the water. The foam becomes thicker and more persistent with each subsequent use. Eliminating the use of swim suits, or rinsing the suits with water alone, will greatly increase the life of your spa water.