I have been living in the same apartment for the last five years. The last 2, years there has been what I would describe as a scummy bacterial growth in the toilet bowl. It is lite tannish, orange in color and resides below the tank’s water line. At the water line, appears to be a “black mildew like growth” that extends to the top of the toilet’s rim.
This stuff stinks to high heaven if I ever forget to flush the toilet after urinating.
If I clean the toilet it re-appears within a week. Dropping a chorinated toilet bowl cleaner tablet will stop it completly until dissolves.
Does anyone know what this is and how to permently stop it.
That sounds like iron staining. Water with as little as .3 ppm or mg/l of Ferrous iron can cause staining from a yellow to dark rusty orangish reddish brown. It could also be IRB (iron reducing bacteria). That causes a clear to the same colored slime. Either will usually wipe off with little effort but somtimes the staining requires a product used to remove them such as Iron Out etc..
A water softener or iron filter removes Ferrous iron but IRB will prevent them for working so it’s important to identify what type iron you have in the water. Disposable cartridge type filters will not work for either type of iron; they only work for Ferric iron which is oxidized Ferrous iron and are called sediment filters.