For the last year I've been on well water for the first time in my life. High iron, manganese and iron bacteria - safe, but tasted eggy and ruined shower heads, dishwashers, clothes, washing machine, kettles...
I just finished installing a whole-house filter & softener system and everyone is delighted. I told my kids that once a month we're going to serve untreated well-water with dinner, so we stay grateful for it.
As a fellow filtered well-water maintainer... just give it time. Even the best filtration systems break down. There are lots of moving parts to keep that water clean. Odds are you'll see or smell that brown water soon enough!
I like this form of parenting. Make your life better for your kids, but reintroduce some challenge so that they learn to appreciate the comforts of life.