Knowing whether it works

A system that was commissioned correctly can drift for months without anyone noticing, because the water still looks fine.

Baseline first

Performance is only meaningful against a recorded starting point: flow, pressure differential and the relevant water quality parameters at commissioning, in writing. Without that, later readings are numbers without a reference.

Watch the differential

Pressure drop across a filter rising at constant flow is the earliest honest signal of fouling, and it costs nothing to log. Most maintenance that happens too late could have been scheduled from this one trend.

Sample properly

Where and when a sample is taken changes the result more than most people expect — straight after a backwash, at the start of a shift, from a dead leg in the pipework. A sampling procedure written down and followed is worth more than a more expensive analysis taken casually.

None of this is specialist work. It is a logbook and the discipline to keep it.

Measuring the wrong thing

It is common to find a site logging parameters that never change and ignoring the ones that drift. Conductivity on a feed that is always the same tells you nothing; differential pressure, recovery ratio and the trend in cleaning frequency tell you almost everything. Reviewing which parameters are actually worth logging is usually the cheapest improvement available.