KH Director IL (12HU)

Industrial Line slide-in unit (12HU) for automated alkalinity (KH) measurement and control. Uses precision pH-based titration for accurate, repeatable results — up to 24 measurements per day. Automatically adjusts dosing quantities to maintain stable KH levels. Works with marine and freshwater aquariums. Connects via PAB (ProfiLux Aquatic Bus).

The KH Director® IL is the Industrial Line version of GHL’s proven KH Director® — identical technology, firmware, and measurement precision in a robust 12HU aluminum slide-in housing designed for professional installations.

Alkalinity is the single most important parameter to keep stable in a reef aquarium. The KH Director® measures it automatically using precision pH-based titration — the gold standard in KH measurement. Up to 24 fully automatic measurements per day keep you informed around the clock, and manual tests can be triggered at any time.

Beyond measurement, the KH Director® actively controls your alkalinity: it automatically adjusts dosing pump quantities based on measured deviations to maintain a stable KH setpoint. Choose between Add-On control mode (fixed ml adjustment), Adaptive control mode (percentage-based adjustment), or Target Value control mode — compatible with Balling®, Triton®, and other dosing methods.

Combine with the ION Director® IL for complete water parameter automation — measure and control Ca, Mg, K, Na, and NO3 alongside alkalinity.

Requires a GHL Doser 2.x / 3.x Standalone or a ProfiLux® 4 Aquarium Controller with a Doser 2.x / 3.x Extension (EXT). Three dosing pump heads are used for the measurement process (sample water, reagent, and waste).

Scope of delivery

These items are included:

• KH Director® IL slide-in unit with integrated measuring cell
• pH sensor, specially designed for the KHD, incl. calibration fluids pH 4 and pH 7
• Reagent fluid 500 mL
• Silicone tube 5 m
• Flex-PVC tube 70 cm
• Power supply splitter cable

Product dimensions

L × W × H: 295 mm × 119.6 mm × 112 mm (11.6″ × 4.7″ × 4.4″)