The yellow is iron stains. You can get "Iron Out" in any grocery store, and most people from the country will tell you it WORKS!
Some times it is put in a washing machine, too. If you are on well water, with iron, NEVER use liquid bleach it makes the iron come out of solution and gives it the ability to stain.
If you live in a very old area you might have old iron pipes that are rusting on the in side, and causing the problem, too. If so follow the country people's rules above, or go to the laundry mat, or call for water treatment!
Some times it is put in a washing machine, too. If you are on well water, with iron, NEVER use liquid bleach it makes the iron come out of solution and gives it the ability to stain.
If you live in a very old area you might have old iron pipes that are rusting on the in side, and causing the problem, too. If so follow the country people's rules above, or go to the laundry mat, or call for water treatment!