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I have done a microbial count. What does it mean?

The total bacteria count is one of the key indicators in the field of hygiene management. It indicates how many microorganisms are present in a sample.

Bacteriological water analysis is a method of analyzing water to estimate the numbers of bacteria present and, if needed, to find out what sort of bacteria they are


It represents one aspect of water quality. It is a microbiological analytical procedure that uses samples of water and from these samples determines the concentration of bacteria. It is then possible to draw inferences about the suitability of the water for use from these concentrations. This process is used, for example, to routinely confirm that water is safe for human consumption or that bathing and recreational waters are safe to use.

The interpretation and the action trigger levels for different waters vary depending on the use made of the water. Whilst very stringent levels apply to drinking water, more relaxed levels apply to marine bathing waters, where much lower volumes of water are expected to be ingested by users.

Drinking water levels

The bacteria count (aerobic plate count) should not be above 100 < ml for general drinking water norms. 

The effect of purification on the bacteria count

Reverse Osmosis removes bacteria up to 99,9%. To be 100% sure every bacteria is removed, a UV light is often supplied when treating ground/surface water. No membrane technology is able to remove bacteria for 100%. 

High levels of bacterial count from kitchen faucet

High levels can occur at any faucet, also after a purifier. This phenomenon occurs when unsanitized tubes are used, or if the top of the faucet is touched. By touching the faucet, the bacteria are able to travel into the water supply. It is therefore recommended to sanitize your faucet well. 

High levels of bacterial count from tank

High levels of bacterial count can occur even in the clean water tank. The bacteria count can occur from unsanitized installation. To ensure water is always safe to drink, we work with UV-light disinfection as a post-treatment. Not sure whether your tank is clean? We recommend these two options:

  • Disconnect the purifier and rinse all pipes with chlorine or hydrogen peroxide (1-2%).  Leave for 5 minutes and rinse everything.
  • Shock cleaning method (takes 14 days)