Taylorjm
Active Member
I looked at the MSDS:
https://images.homedepot-static.com/catalog/pdfImages/f2/f2450f9f-f527-4720-a8b1-1c504df4f40f.pdf
Main active ingredient 20% hydrochloric acid (muriatic acid).
Don't breath the fumes, but it would probably be effective.
It's actually oxalic acid that will get rid of the iron stains. It used to be in "the works" toilet bowl cleaner, and it's also found in some wood deck cleaners. You can also buy the oxalic acid powder on amazon for a few dollars and mix 63 grams to a gallon of water and let it soak in the filter housing, then pour it back into the gallon containers and can use it over and over again. Some baking soda added to it will neutralize it before getting rid of it when it won't clean any more. It's not near as toxic as the toilet bowl cleaner, and not as bad of fumes. You are right, the toilet bowl cleaner does put off some nasty fumes. And the fumes are even stronger when it comes in contact with the iron stains.