I have hard water too! Its awful! From years of trial and error, and doing a lot of research, this is what I've found: If your brushes are natural hair(really it goes for synthetic too), washing them with clarifying shampoo or any shampoo for that matter, that has sodium laurel(laureth) sulfate(s) in it is going to really damage your brushes----the same way it really damages your hair. [there's a lot of info in the web about how bad SLS's are]
What I use for both my brushes and my hair is a good SLS-free shampoo, and then a quick rinse with apple cider vinegar. It sounds strange, I know, but the vinegar neutralizes all the harsh crap in hard water. [there's also a lot of good info out there about vinegar rinses]. I use a solution of 1 tsp. vinegar to 1 cup water. I wash my brushes with Burt's Bees shampoo (SLS-free) and then give them a quick swish in the vinegar solution, then rise out. It smells to high heaven, but I promise, the smell goes away when the brushes dry.
Same for my hair too. The hard water was making it dull and lifeless, and if I do a vinegar rinse 2-3 times a week, it makes it much smoother, shiny, and bouncy.
sory for the long post! HTH!
