Hardwater

That is why it takes more soap to make a good lather when using hardwater.

The greater availability of nutrients in hardwater streams stimulated more abundant fungal biomass and fungal activity and resulted in a more diverse fungal species assemblage.

In experiments which seem appropriate to this topic, Abel and Bârlocher (1984) found that cadmium was more toxic to aquatic hyphomycetes in softwater with low calcium concentrations than in hardwater with high calcium levels.