Measuring & Control — Bluelab

The striking thing about this page is not which meters are on it but how much maintenance sits beside them. Calibration solutions, storage fluid, cleaning kits and separate probes make up roughly half the range. That is not an upsell but how this brand works: a pH meter is an instrument with a wearing part, and you replace that part rather than the meter.

Four kinds of measurement, four form factors

The pens come for pH, for EC, as a soil pen and as a Combo reading both. The Truncheon is an EC meter without a screen that you leave sitting in the water and read off an LED bar. The Pulse reads in the substrate itself, so moisture, EC and temperature in the pot rather than in the feed water. The Guardian is a monitor that stays mounted at the tank and reads continuously, and there is a wifi version.

The probe is the consumable

On the meters with a replaceable probe, the Leap and the standard pH probe among them, the probe is the part that wears out. Replacing it usually costs less than a new meter, and that is why we stock them separately.

Never store a pH probe dry

This is the mistake that kills most pH meters early. A pH probe has to stay wet, in KCl storage fluid and not in deionised water. Storing it dry between readings costs you the probe, and it is not a fault you can see: it goes slow first and wrong afterwards. That is why we stock KCl alongside every meter with a separate probe.

Frequently asked questions

How often should I calibrate?
More often than most people do. For pH, before each run of readings is normal; for EC, less often. Calibration fluid degrades once opened, so do not buy more than you will use.

What is the difference between the Truncheon and an EC pen?
The Truncheon is meant to stay in the tank and be read at a glance, the pen to be carried around. The measuring principle and the upkeep are comparable.

Does the Pulse read the same as an EC pen?
No. The Pulse reads in the substrate, a pen reads in liquid. The two figures are not directly comparable.