On Monday, January 30, 2017 at 9:07:36 AM UTC-8, Oren wrote:
On Mon, 30 Jan 2017 10:39:41 -0600, "Terry Coombs"
wrote:

As a laundry additive ... we have very hard water , and I've noticed that
my work clothes are getting stains that don't come out . I do know rhat when
they quit using phosphates in detergents and cleaning solutions they became
less effective .
I have a box of TSP (the real stuff) and I'm considering adding some to a
load of my work clothes to see if this will make my detergent more effective
. Recommendations of how much to use are welcome ...

I don't measure the TSP (red box - real stuff), just sprinkle some in
the washer. Guessing less than 1/3 cup. YMMV

After you add the TSP let the load soak for about one hour.