I recently did a hands-on trial of the LaMotte BrewLab Plus water test kit. I was skeptical going into it with all the "chemistry stuff" involved with test tubes and droplets of solution A and solution B. But I was surprised how it was actually kind of fun, and the distinct color changes as you reached the threshhold for measurement was very obvious. So I felt like it was able to give solid results that I could bank on and have been able to use my tap water (post 3-filter system) + brewing salts to get back in the ballpark of where I was with distilled water + brewing salts.
It's a bit pricey, but it has enough chemicals to do about 50 tests. So if you don't want to own it outright yourself, it's certainly an option to split the cost with a buddy or a club. Below is a link to my detailed review.
http://www.homebrewfinds.com/2018/09/hands-on-review-lamotte-brew-lab-plus-water-test-kit.html
It's a bit pricey, but it has enough chemicals to do about 50 tests. So if you don't want to own it outright yourself, it's certainly an option to split the cost with a buddy or a club. Below is a link to my detailed review.
http://www.homebrewfinds.com/2018/09/hands-on-review-lamotte-brew-lab-plus-water-test-kit.html