What does it mean when your toilet bowl turns black?

The glaze of the toilet lavatories may turn black after a long time of use. The blackening of the glaze of the vitreous china toilet may be caused by scale, stains or bacteria. It is very easy to repair. When the glaze of my toilet turned black, I followed the following tips and it was easy to fix.
1. Do daily cleaning, sterilization and descaling. You can put a napkin on the seat, spray lemon water, cover it for a while, rinse it and dry it, which can effectively remove bacteria. Put toilet cleaner in the water tank, do daily cleaning, sterilization and descaling. To prevent bacteria from growing, you can wear rubber gloves to clean the toilet.
2. Cleaning method for lightly dirty water closet For toilets that are not too dirty, you can put toilet paper on the inner wall of the toilet one by one, then spray detergent or leftover cola, let it stand for an hour, rinse it with clean water, and finally scrub it gently with a brush. This method not only does not require laborious scrubbing, but also has excellent cleaning effects.
3. Descaling with ceramic toilet cleaner Pour 2 spoons of this product (about 40-50 grams), pour about 0.5 liters of warm water, wait for 15 minutes, and then rinse with a large amount of this product. If stubborn stains have formed, you can use it with a vinegar solution, soak it fully, and then scrub it with a brush. The easily overlooked outer bottom of the toilet can also be cleaned in the same way and wiped dry with a cloth.
4. Descaling with detergent For the yellow dirt formed on the edge of the toilet, you can tie a used nylon sock to one end of a wooden stick and dip it in a foaming detergent to scrub. Clean it once a month to keep the toilet clean. The specific method is: first put an appropriate amount of water in the toilet bowl, use