Hello Dear,
I suppose someone could "waterproof" with soap. (repeated use, and poor rinsing )
Or detergent, and fabric softener (repeated use, and poor rinsing) Oh and lets not forget the Dryer sheets, if they don't work for the Dryer...they do work well for ant repellant! LOL
BTW,
not all soap is made with Tallow, thats only one of many combinations of fatty acids that can be used. You would'nt get a lot of sudsing, or cleansing with 100% Tallow anyway. (other's needed, or blended with, to achieve that)
Back to the Suds,
I used the STPP as a last min thought, with Marks dilemma in mind.
(the dishpan with soap, and my water here being similar in hardness to his)
Point being... weather soap, or detergent, the STPP "may" be what is needed for Mark to achieve the desired suds level he's looking for.
Since most commercial detergents are now adding suds suppressants...
(Silicone being one, as is the case with modern Ivory Snow, and others)
the only alternative "may" be the surfactants used in some Mexican detergents, that "possibly" do not add a suppressant. Or with the old school, simple surfactant of... soap and "Phosphates" as Sudsmaster, and Maytagbear suggested up thread.
Mark has'nt chimed in yet, as he probably has tried all this already, and we are spinning our wheels for nothing! LOL