I guess it depends on how eco-friendly you want to be, but the cheapest and fastest thing I have found is a product called "the works" at my local dollar store. You don't even want to know what the toilet looked like when I moved in my home before I cleaned it. I may have been the first. It works really well on iron and on hard water stains. I actually put half of the bottle in the bowl, swished it around good and left it sit over night. Another good swish and scrub in the morning and it came right out.

PS- I am not buying the story from the PO's of the house that it was the water, because it has never looked that way again or even close. LOL.

There is a product called iron out, that you can buy in any hardware store and some grocery stores. It has a bit of a sulphur odor to it, but it will clean out the toilet, can be used in laundry for rust stains, and can be used in a badly stained dishwasher. When we lived in Mn, our well water had a lot of iron in it. We did eventually put in a water filtration system, but until then, Iron Out was one of my very best friends.

I hadn't thought about Iron Out. I have used it on my laundry a lot, but never thought about using it in my toilet. Duh. I guess it pays to think outside the box. LOL.

It would definitely be worth a try. It works great for getting iron stains out of laundry and off of sinks and such.

How do you clean your toilet bowl now: I use Lysol toilet bow cleaner that we get at Costco. It is a high percentage of hydrochloric acid and that disolves iron quite will.