We always had a ring of magnesium in our toilet and it has done the job, finally something that works!
Even the inside of the tank appears cleaner!
So far it’s working great!
So, I always prepare myself to be disappointed by great things found on the internet. When the Krazy Klean arrived I put it in the toilets and left for 10 days. In 10 days of the water just sitting there I would have a ring that it very hard to remove. When I returned I went to check...no ring...3 weeks later still no ring. I have to say this one was a great purchase. I do not know what this does that my water softener can't do...but it works great.
We put these in three of our toilets about a month ago and are seeing a real difference in how long it is between cleanings now. Very happy with the results!