Salt and dead algae foam. This is what you see at the beach on a windy day that they call sea foam. Soaps will enhance this but just the dead algae and salt alone will foam.
If the SH is not rinsed off after Softwashing.....will it (the salt) damage the plants and lawn later when it does rain and rinses off... or does it just become inert over time and of so how long?
Thanks
Ron