GHL KH Director – Monitor, maintain and control Alkalinity with ease
The upkeep of Alkalinity is the most important aspect of reef keeping. If you’re looking to achieve exceptional coral growth, Alkalinity testing is a must!
The KH Director results from more than 2 years of research and development into the automated Alkalinity monitoring and control department. As always, we’ve stuck to our fundamental belief in high quality and exceptional reliability to bring you a product that is built to last. Featuring a patent-pending design, KHD utilizes lab-grade quality test standards to provide precise results every time. KHD is built to provide aquarium hobbyists and professionals with a safe and reliable Alkalinity control product that presents great value, functionality, and practicality.
Automated Alkalinity monitoring and control
KH Director uses a modified pH probe to provide KH values. In terms of the KH test process, the 3 adapters on the KHD each connect to an available GHL Doser 2 or 2.1 dosing unit. One pump is used to feed tank water into the KHD. The second pump feeds the KHD with reagent fluid. The third pump extracts the test sample and used reagent fluid after a completed test, then dispenses it into a waste bin.
As tests occur, the 3 pumps automatically perform their assigned tasks and report the results onto a viewable data logging chart. This data is then viewable on myGHL, ProfiLux Touch, ProfiLux display, and additional external display unit.
Lab grade KH measurement accuracy
Measure your Alkalinity with lab-grade accuracy. With only a 100 ml water sample, KH Director® can provide measurement values with 0.1 ° dKH accuracy.
Extreme efficiency and cost-effectiveness
Here at GHL we understand the importance of on-going costs involved with automated KH monitoring and control. For the KH Director it was especially important to consider these costs and develop a highly-efficient, cost-effective product. A single 1000ml bottle of reagent can last for up to 3 months when testing is performed 4x per day at a KH value of 8. The pH electrode used by the KH Director was specially designed for KH measurement and has an average lifespan of 1 – 2 years.
Requirements
To operate the KH Director, you will need to have at least 3 available dosing pump motors. KH Director gives you the flexibility to run the device in one of two ways.
- KHD can be connected to a Standalone Doser 2.1 or 2.0

- KHD can be connected to a Slave Doser 2.1 or 2.0 and ProfiLux 3 or 4 controller

Seamless integration w/ GHL system
Through the use of the PAB (ProfiLux Aquatic Bus) connection, KH Director® seamlessly integrates into the modular GHL aquarium system. The PAB connection ensures interference-free communication with other GHL PAB-devices such as the GHL Doser 2.1 or the ProfiLux® 4.
Backward compatibility
We want you to grow with us! Even the ProfiLux 3 / 3.1 and GHL Doser 2.0 will be compatible with the KH Director.
What’s included
KH Director / Doser 2.1 set includes the following:
- KH Director device w/ integrated measuring cell
- Specially designed pH electrode for KH measurement
- Calibration fluid
- 500ml reagent bottle
- Silicone hose
- Power supply splitter cable
- PAB-cable (50 cm / 19.6″ length)
- GHL Doser 2.1 SA, 4 pumps, white
- 24V Power supply
- 8x Plastic tubing adapters
- 6ft USB cable
GCC, GHL Connect App, Cloud Service

GHL Devices are easily accessible via the free PC software GCC , GHL Connect app and cloud service myGHL. (> learn more).
Reagent Consumption
A single 1000ml bottle of reagent can last for up to 3 months when testing is performed 4x per day at a KH value of 8.
Support
Do you have questions or need technical support?
We’re here to help. First begin by following a few tips:
You have questions about the operation or for system setup?
- A good start is visiting our Knowledge Base and our FAQs.
- Download our manuals and tutorials. In most cases, the answers to your questions are answered in there. You´ll find them listed in our download center.
- Check out our extensive videos.
Still have questions?
- Take advantage of our extensive GHL support forum. Here, you will find topics and questions that have already been answered by our support team and/or customers. Tips and suggestions can also be found here. If this does not help, then please ask your question there. You will have direct contact with the GHL team and to many users, who can quickly help you.
Do you have a complaint or a defective product?
- Your first contact should always be the dealer from whom you purchased the products.
- In case you bought directly from GHL please contact us directly via our ticket system.
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