The ColiMinder can measure any type of sample without pre-treatment. It has no problem with suspended solids or turbid samples. Even fluctuating background fluorescence has no effect on the measurement result.
Its robustness towards environmental influences, like temperature or humidity, is evident in installations like Stonecutter Island Sewage Treatment Plant in Hong Kong, where it has been monitoring effluent 24/7 since 2017 without any issues. Its housing is IP65 protection class, measurement temperature range is 0°C to 42°C.