Review on 🚽 Ty-D-Bol Free and Clear Toilet Cleaner: Powerful Cleaning and Deodorizing for Pristine Bathrooms - Pack of 6 by Marcos Woody

They're expensive but worth the money - they don't contain bleach which is hard to find. Our plumber told us that bleach pills, whether dangling in the toilet tank or dangling from the rim of the bowl, will corrode the toilet's rubber seals. Once those gaskets start to fail you have to take the entire toilet(!) off the floor (no thanks) to replace the gaskets as they start leaking - both on the bathroom floor and UNDER the floor. So make sure you buy anything that can hang in your toilet OR tank WITHOUT BLEACH. He said it can be cleaned with bleach because you don't leave it wet.