If mold has recently appeared on your caulking in your shower, you can get rid of it by following the tips below. These steps work best if the mold is mild and has just shown up in your shower.
Supplies
You are going to need some bleach, a spray bottle and access to water. You are also going to need a bucket that you can fill up with warm soapy water as well as a scrub brush.
You don't want to breathe in mold spores, and bleach can smell really strong and stain your clothing. Put on protective eyewear as well as a mask to ensure that you don't breath in the mold spores or get splattered with the bleach. Wear clothing you don't mind ruining and that covers your entire body. You should also wear gloves.
Preparation
Take your bucket and fill it up about half way with warm water, then add a few drops of dish soap and a little more water until you have a bucket full of suds.
Take the spray bottle, and fill it up with bleach. Do not add water to this solution. The bottle should be filled with undiluted bleach. The bleach will kill the mold, which is why you shouldn't dilute it down with water and weaken it.
Cleaning
First, take the bucket filled with warm soapy water into your shower area. Dip a rag into the soapy water. Use that rag to clean all the caulking that has mold growing on it. Work the rag in a circular motion to dislodge as much mold as possible. Ring out and rag as you work. This should loosen up the mold spores and remove some of them.
Once you have washed the caulking with the soapy water, it is time to use the bleach. If possible, turn on the fan in your bathroom and open up the window before you use the bleach; the odor can be overwhelming. If you have any rugs or coverings inside of your shower, take them out so that the bleach will not discolor them.
When everything is prepared, spray the bleach directly onto the affected caulking. Spray generously; the caulking should be dripping wet with bleach. Then, leave the room and let the bleach sit and soak into the caulking and kill the mold for at least twenty minutes.
After twenty minutes, come back and use the scrub brush to dislodge any remaining mold spores. Do not get too rough or you could damage the caulking.
Finally, when you are done scrubbing, wash the area with a new mixture of soapy water. Use a new rag as well; you don't want any mold spores that were on the rag to be transferred back onto the clean caulking. This will get rid of any bleach that is left behind. Allow the caulking to air dry.
Immediately wash all rags used as well as the scrub brush or dispose of them. You don't want to transfer the mold spores to your next cleaning project. You should also immediately wash your cleaning clothes; don't sit down anywhere, you could have bleach or mold spores on your clothing.
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