Including filter system and high-performance HPC Bacteria filter.
HPC bacteria are a broad group of naturally occurring microorganisms that can show up in household water and plumbing. You may also see this referred to as heterotrophic plate count, a lab method used to estimate general bacterial growth rather than identifying one specific organism. In homes around Arran, homeowners commonly notice signs such as musty smells, slimy deposits, or faster biofilm buildup on faucet aerators and showerheads when these conditions exist.
Levels measured by heterotrophic plate count tend to increase when water sits in pipes, when sediment or organic material is present, or when plumbing allows biofilm to form. These situations can produce changes in taste or odor alongside broader bacterial activity. While many heterotrophic bacteria aren’t known to cause disease, elevated HPC bacteria are often a useful signal that a household water system needs attention. In Arran, taking a whole-house view helps treat the water as it enters your home and reduces the chances of regrowth further downstream.
To reduce HPC bacteria throughout a residence, a whole-house ultraviolet (UV) disinfection system is generally the most effective single-filter solution. UV inactivates microorganisms as water flows through a stainless chamber exposed to a UV lamp, treating water in real time without adding chemicals or altering taste. When installed at the main water entry for an Arran home, UV protection covers every tap, shower, and appliance on your property.
For dependable UV performance, the water feeding the unit must be clear enough for the light to penetrate—heavy sediment, iron, or cloudiness can shield microbes from the lamp. That’s why whole-house UV systems are often paired with prefiltration, while the UV stage remains the primary technology targeting microorganisms like HPC bacteria. Correct sizing for your home’s flow rate and routine lamp and sleeve maintenance keep the system working as intended; Mr. Pure Water can help Arran homeowners select and install a whole-house UV system matched to their plumbing so heterotrophic plate count is better controlled at the source.