paint section of the hardware store and buy it in a box (TSP
KOOL @!!
That is not the best form of phosphate to use in your dishwasher and washing machine.
This is where I order the kind of phosphate that is designed specifically for those purposes. I have been using for years.
https://www.soapgoods.com/Sodium-Tripolyphosphate-Light-Density-STPP-p-1267.html.
TSP is phosphate free.
Really.