Have you ever wondered why your toilet bowl cleaner is always blue? I have. And for some reason, I'm not a fan. But that's OK, because now I make my own toilet bowl cleaner too. And I've gotta tell you, it works just as good if not better! (P.S. - It's not blue.)
All you need is baking soda, Borax, vinegar & a toilet brush! Sprinkle a generous amount of baking soda & Borax all over your toilet bowl. Next pour some vinegar directly into the bowl. When the majority of the fizzing stops, scrub with your toilet brush. Don't be alarmed if it starts to fizz again, after all, you're mixing it with some of the baking soda that was above the water line. Just be sure you let it sit a while to continue to work on any stubborn spots (especially ones you can't reach).