So this has nothing to do with rug hooking, but I’ve talked about this solution for my very hard water during my Live! Lessons and I needed a place to send people.
I used to store the mixture in Mason jars. Do NOT do that. It can get hard and then it is hard to get it out. If you click on the link in the article for the FAQ’s you will see that the original author found this out also and now stores the powder in a bowl like container so it is easier to stir on a regular basis. This will keep it from clumping up into one hard block.