The development of hard water stains can make your toilet increasingly harder to keep clean after some time. Hard water can have metals such as iron, magnesium, and calcium dissolved within it. Most water has differing concentrations of minerals dissolved within the water.
For example, serratia marcescens is a bacterial species that leaves a pink ring around the toilet and can be confused with hard water containing iron. Also, certain types of microbes have a color which can be confused with hard water. This concentration of microbes leads to the ring around the toilet. The water evaporates very slowly and allows the microbes to concentrate around the edges of the water and grow under these perfect conditions. The water that is in contact with the sides of the toilet bowl is a great environment for the growth of fungi, mold, bacteria, and viruses. Each of these microbes multiplies and reproduces and cling to the toilet bowl and become concentrated together.
Mold, fungi, bacteria and viruses grow in the water in our toilets. This can easily be confused with hard water stains. The growth of microorganisms such as mold, fungi, bacteria and viruses can often cause the appearance of a ring around the edge of the toilet water. Toilet bowl stains have many different causes, but the 2 most common causes are microbes and hard water.
