Unbenounced to me, apparently we can not use toilet tablets with the specific toilets we have in our new house. After using them for a month or so, we noticed it was causing damage and after Googling our toilet model, we discovered that sure enough, we were correct.Great! Those tablets are total lifesavers! Luckily, I discovered a solution to this problem! Scrubbing Bubbles makes a toilet cleaning gel that works amazing! One a week I just push a new dot of gel and it's good as new!