Toilet bowl stain - x-post from plumbing
I have a question about the toilet we got in the guest bathroom of the house we bought recently. The previous owner lived their alone until she passed and the house was sold to us by surviving children and we got it that this bathroom was not used very often. The toilet bowl developed "a ring stain" where water sits that we don't seem to be able to get rid off. It is a good functioning low flow toilet and I don't want to waste it if I can make this stain go away. We tried - all kinds of cleaners, bleach,soda and finally murietic acid solution (for this treatment we had the bowl taken off the pipe and treated in the backyard). Nothing seems to work. The ring is some sort of calcified deposits, you can feel it upon touch, its kinda rough.
Another interesting feature of this toilet is that upon a single flush bowl fills and siphons at least 3 times, which initially made us think it is a flaw or something is wrong with the drain, but it turns out it doesn't waste more water since it is a single flush and keeps waste elimination more efficient - I don't remember seeing such 3-in-1 flush anywhere before. Am I wrong in my assumptions?
This kohler model is from mid 1990's.