The
soap scum or snot is a bacterial growth from the water that just loves the
soap. I used to get it when I used Turtle Wax
soap products and again when I used
Kleen-Rite soap products, but only real bad at one car wash. I’ve tried the copper pipe thing, didn’t really work very well. I had the use a HTH 1” swimming pool bleach pellet to get it under control. I used to hang a 1” swimming pool bleach pellet in a 35mm film canister with holes drilled in it in the
soap tank, it’d last about 2 weeks before I had to add another bleach pellet. When I switched to
JBS soap products it stopped. The inexpensive
soap products don’t have enough algaecides in the water to prevent the bacterial bloom or growth from occurring