For toilets I have this thing about clean without chemicals. This will help dissolve scale from hard water and keeps other nice stuff from taking over.

pour 4 cups vinegar in the bowl ans swish around, wait about a minute then add 1 cup baking soda, the bubbling action will work its way up the bowl.

  let this happen and come back in a few minutes, then I swish it around and flush it down ... This works great!