Including filter system and high-performance HPC Bacteria filter.
HPC bacteria are a wide-ranging group of naturally occurring microorganisms that can show up in household water and inside plumbing. You may also see this referred to as heterotrophic plate count, which is the laboratory technique used to estimate overall bacterial growth rather than identify a single pathogen. In Littman homes, these results often indicate conditions where bacteria can multiply — homeowners sometimes spot musty smells, slimy buildup, or faster biofilm formation on faucets and showerheads when general bacterial activity is present.
Heterotrophic plate count readings can increase when water stands in pipes, when sediment or organic material is available as food, or where plumbing allows biofilm to form. You might notice subtle changes in taste or odor along with that general bacterial presence. While many heterotrophic bacteria aren’t classified as direct disease threats, elevated HPC bacteria often point to a water system that needs attention. Taking a whole-house view in Littman helps treat incoming water and reduce conditions that allow regrowth further down the plumbing system.
To reduce HPC bacteria throughout a Littman residence, a whole-house ultraviolet (UV) disinfection system is commonly the most effective single filter–style option. 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 where water enters your Littman home, a UV system protects every tap, shower, and appliance from heterotrophic plate count concerns.
For UV to work reliably in Littman plumbing, the water feeding the unit must be clear enough for the light to reach microbes — heavy sediment, iron, or cloudiness can block the lamp. That’s why many whole-house installations combine UV with prefiltration, although 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 performing; Mr. Pure Water can assess your Littman plumbing and recommend the right whole-house UV setup to better control heterotrophic plate count at the point of entry.