Bluelab Conductivity Probe Cleaning Kit - Keep Your Truncheon Reading True
Best for: owners of the Bluelab Truncheon EC/CF/PPM meter who want to stop mineral scale and algae throwing off their readings.
Our thoughts
Cheap, boring, and exactly what a Truncheon owner needs once a season. The probe tip on any conductivity meter picks up scale and gunk from nutrient solution over time, and a drifting Truncheon is worse than no Truncheon at all because you won't know it's wrong. This kit sorts that out for less than the cost of a decent coffee.
The Bluelab Truncheon is the classic analog conductivity meter that floats in your reservoir and gives you an EC, CF or PPM reading straight off a dial, with no batteries or calibration screen involved. Its accuracy relies entirely on a clean probe tip - mineral deposits and biofilm from nutrient solution build up on the conductivity ring over time and skew the reading low or erratic. This cleaning kit contains the cleaning solution and materials needed to strip that build-up off the probe and get it reading true again.
How it compares
It's a maintenance consumable rather than a testing device, so the real comparison is against not maintaining your probe at all.
- Versus doing nothing, a dirty Truncheon probe will quietly under-read your EC, leading to overfeeding without you realising - this kit is cheap insurance against that.
- Versus a generic vinegar-and-water DIY clean, Bluelab's own solution is formulated specifically to dissolve mineral scale without damaging the probe surface.
- Versus Bluelab's combined pH & EC cleaning kit for digital meters like the Combo or Maestro, this kit is Truncheon-specific and doesn't include pH calibration solution, since the Truncheon has no pH function.
It's a small, sensible spend that keeps an otherwise long-lived analog meter accurate for years.
Usage guidance
A quick clean every few weeks to a couple of months, depending on how hard your nutrient solution is on the probe, is enough for most growers.
When to clean
If your Truncheon reading looks low compared to what you'd expect from your mix, or the probe tip looks discoloured or filmy, it's time to clean it.
How to clean
Follow the instructions included in the kit to soak and wipe the probe tip with the supplied cleaning solution, removing scale and film from the conductivity ring before rinsing and returning the Truncheon to use.
Routine maintenance
Rinse the probe in clean water after each use in strong nutrient solution to slow down scale build-up between full cleans.
Technical specifications
- Compatible with: Bluelab Truncheon EC/CF/PPM meter
- Kit type: probe cleaning solution and cleaning materials
- Function: removes mineral scale and biofilm from the conductivity probe tip
- Calibration solution included: no - Truncheon is a direct-read analog meter
- Recommended use: periodic maintenance, every few weeks to months depending on use
Who this is for
- Truncheon owners who've noticed readings drifting or looking inconsistent
- Hydroponic growers who rely on their Truncheon as their main EC check
- Anyone wanting to protect the accuracy of an otherwise low-maintenance analog meter
- Growers stocking up on consumables alongside their main nutrient and testing kit
Best suited to existing Truncheon owners rather than anyone shopping for a first EC meter.
Our take
This isn't an exciting purchase, but it's the difference between a Truncheon you can trust and one quietly lying to you about your feed strength. For the price, there's no reason to skip it.
Worth picking up alongside your Truncheon, or as soon as your readings start to look off. Does exactly what it should, day in, day out.
