Barkeeper's Friend Cleanser.....First flush toilet, turn water off so toilet won't refill. Pour cleanser in and around rust to make a paste with cleanser. Let cleanser sit on rust for a while or until you think rust may be gone, wipe off. Scrubbing bubbles may work too. I swear by this product but the key in it working is not to add a lot of water. Use dry towel to wipe away, but allow it to sit for a while as well! Just try to get toilet water as low as possible. You can scoop water out with a small cup.
BLEACH
It takes an hour for an iron to rust
Descaler is a powerful yet safe cleaner for rust and limescale.
Acid, to help remove calcium carbonate and rust deposits.
Probably nothing wrong with the toilet. It is more likely that your pipes are full of rust or mineral deposits.
Rust stains on porcelain are almost impossible to remove because the rust has most often combined chemically with the glaze and cannot be removed without removing the glaze. You could try acids (phosphoric acid for example).
NO!!! Because they are made of copper NOT iron.
you are wrong. cats can be trained to use the toilet. it takes about 2 weekz of trainig
use CLR or anything with oxi clean, kaboom works pretty well.
it might cause an explosion or it might cause an oxidation and the rust of pipes.
Rust.
The time it takes to assemble and install a new toilet is about one hour.