For treating bronze disease, a good way to treat it is a 3-5 percent solution of sodium sesquicarbonate in distilled water (espescially if your water is chlorinated you need to have distilled water).
Sodium sesquicarbonate can be made by mixing washing soda and baking soda together.
However, washing soda is hard to come by.
So it is better to make it yourself.
Handy video by the nice channel NileRed (not a coin channel).
https://www.youtube.com/watch?v=cpGEc-pLXN4
Hope this is helpful.
Jonathan