In a saucepan, add 2 Tbsp. of cornstarch to 1 cup of water. Stir until dissolved. Place mixture on the stove and stir until it comes to a boil. Turn off stove. The mix will become really thick. Let it cool completely.
Then add 5-6 Tbsp. of bleach. It will turn into a gel. If it's thicker or thinner, just adjust water and cornstarch until you get the result you are looking for. Pour mix into an empty squeeze bottle for dispensing. So much cheaper and works great.
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Instead of buying those bleach pen I took an old "Ghost" pen from the books that you get in truck stops to keep busy. I put bleach in an old one that had dried out.
Instead of a bleach pen, since they are expensive and you don't get much for your money, use an old spray bottle with a squirter and put bleach right in the bottle and squirt it on the stains. Sue