Bests & Worsts Reviews from Amazon

According to the instructions I was supposed to use the whole bottle but being that it was so big and that I had 2 toilets needing to be cleaned I only used half. Other than that I followed the instructions, stirring to make sure it was dissolved and then letting it sit overnight. I used a cheap (new) toilet brush from the dollar store to scrub the rust off the sides before flushing. I took these "Before" and "after" photos to compare and I was pleasantly surprised. The toilet tank is from the 1960's and I doubt it's been cleaned within the last few decades. In the "after" photo you can see that there is still some rust leftover but large chunks fell off the sides and can be seen on the bottom of the tank.