What is the best way to remove a ring in the toilet bowl of a new Kohler toilet, In a very hard water area?

Things you'll need.
New toilet bowl bolts, wax ring, toilet flex supply line (if you don't plan on re-usings old) , crescent wrench, channel locks, plastic cup, newspaper, hack saw, towel, protective gloves (latex, vinyl).

First thing is to turn off the water supply to the toilet. Flush your toilet and hold down the lever to get as much water out of the tank as possible. Now take a plastic cup and scoop out the remaining water in bowl, throw into tub or sink.

Take your crescent wrench and un-bolt tank from floor. If bolts spin, I suggest just cutting them right below the nut, being careful not to scratch or break your toilet. Your toilet will break or crack if your put to much pressure on it, the most common spot for a crack is by the bolt holes. Dissconect supply line from tank holding cup below it to catch the water, if supply line is flex you can leave attached to shut-off valve, if rigid, remove from shut-off valve. Use towel to wipe up water.

Place newspaper out on floor. Stand over toilet facing the tank, your legs on either side of bowl, grab toilet right in front of tank on the bowl. pick straight up, your going to be hunched over while your carrying the toilet and walking like a penguin, just try to keep toilet level as you carry to newspaper.

Remove old seal from bottom of toilet and around toilet drain. Wear gloves and put spoils into plastic bag. Use screw driver to scrape any chunks up. Clean area. Remove old bolts from toilet ring and place new ones in. If toilet ring is broke, call a plumber. Place new wax ring on toilet ring. Make sure bolts are pointing straight up. Get toilet above bolts and lower slowly guiding bolts through toilet holes. After toilet is on, push with light steady pressure straight down to help wax ring spread out even and make new seal. If toilet is leaning towards wall as you push then compensate to have it lower level as possible. Never use a cold wax ring, have it at room temperature. After its lowered sit on toilet for a minute.

Remove any wax that has oozed out and place nuts on bolts, with washers going on first. Hand tighten both sides, then take crescent wrench and tighten down slowly alternating sides, a couple turns on one side then a couple on the other making the toilet set level and ensuring a good seal.
Do not over tighten As it gets harder to turn nut, take your index and thumb and pinch the end of the wrench. Hold with enough force to just hold the wrench, tighten until your fingers slip off. That's the best way I can describe how to tighten bolts safely with out damaging your toilet, if there is a leak you may need to tighten a bit more, use your best judgment. Use hack saw to cut-off excess of bolt,

Attach your supply line and turn water back on slowly. Test for leaks, if no leaks your good.

Do not caulk around your toilet: all that does is turn a leak into a disaster by keeping it hidden from you, Eventually your sub floor will rot and you will have a huge repair bill.

Other Tips:
http://www.fixya.com/support/r5204270-slow_shower_drain_fix

http://www.fixya.com/support/r5197305-stop_water_sweat_solder_water_line

http://www.fixya.com/support/r5245506-leaking_shut_off_valve_hard_close_shut