You don’t need a science degree to pick a water conditioner. You just need to know this: hard water is a bully. Your job is to hire a bigger, cooler bully to push it around. Salt-free conditioners and electronic descales are the cool kids. Salt softeners are the grumpy hall monitor.
Now go forth, hydrated reader. May your shower never feel like sandpaper, and may your ice cubes be crystal clear. And if you still have doubts? Drink a glass of tap water. If it tastes like a penny crying, you know what to do.