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FAQ: KH Director

KH Director

About this article

This article will answer the most commonly asked questions about the KH Director.

What is the KH Director?

The KH Director is a water testing device that measures the alkalinity content in saltwater aquariums. Because alkalinity is the most important parameter in reef keeping, a device like the KH Director can help achieve a new level of stability with automated KH testing and dose adjustments.

KH Director, black

How does the KH Director work?
Is a dosing pump required?

Yes, the KH Director requires a dosing pump.

The KH Director works alongside a GHL Doser 2.1 to measure the alkalinity content in your aquarium. It is this dosing pump that is responsible for feeding a water sample to the KHD, feeding reagent solution for the measurement process and draining the waste water from the KHD at the end of each measurement.

How many pump heads does the KHD require?

3 pump heads from a GHL Doser 2.1

Pump #1: Water sample
Pump #2: Reagent fluid
Pump #3: Waste water

How accurate is the KH Director?

The KHD utilizes lab-grade accuracy and measurement practices to provide an accuracy of 0.1° – 0.2° dkH, depending on water sample size.

How many times per day can I measure my KH?

The KH Director can be set to automatically test anywhere between 1 – 24 times per day.

If you wish, you can also run a manual KH measurement on command with a single push of a button.

How much water does the KHD use per test?

80 – 100 mL per test

The KHD features a user-adjustable test sample volume which lets you choose how much water to use for a water sample. In practice, an accuracy of 0.1° dkH is not always necessary. KHD offers the option to reduce the sample volume for each test. An accuracy of 0.2° dkH can still be achieved with a smaller water sample.

How much reagent solution does the KHD use per test?

1 – 3 mL of reagent is used per test.

The amount used will depend on the alkalinity concentration of the tested water sample.

What size reagent bottles are available?

  • 500mL
  • 1000mL
  • 3x 1000mL Reagent set
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How long will the reagent bottles last?

How many tests you get out of each reagent bottle ultimately depends on how often you are testing and the current KH value of the measured water sample. Below is an approximation of tests per bottle.

500mL bottle
If testing 1x per day…
Approx. number of tests: 168
Will last for: 6 months (avg. 8° dkH)

1000mL bottle
If testing 1x per day…
Approx. number of tests: 336
Will last for: 12 months (avg. 8° dkH)

What is the cost per test?

Cost per test will depend on the size reagent bottle you are using. With a 3-bottle reagent set (PL-1592), the cost per test can be as low as .10 cents

What is the life expectancy of the KHD probe?

The pH electrode used by the KH Director was specially designed for KH measurement and has an average lifespan of 1 – 2 years.

Can I chart and log KHD test results?


Measurement results can be automatically logged (in myGHL) by the primary device controlling the KHD. This data can late be viewed on your platform of choice; GHL Connect app or myGHL website.

See the most recent test results or view past results to get a better understanding of how your KH level has changed over time. With KHD data logging, you can see today’s results, last week or month’s results and beyond.

Can the KHD control a calcium reactor?


With a ProfiLux controller and KHD, the KHD can automatically adjust the pH value inside your calcium reactor based on the outcome of each KH test result. With this kind of setup, the ProfiLux is the primary means of calcium reactor control. If you wish to have the KHD involved, the KHD becomes the secondary level of calcium reactor control. Depending on the outcome of each KH test, the KHD can automatically adjust the target pH value inside the calcium reactor for increased stability.

Can the KHD adjust my dosing schedule?


Aside from the KHD’s measurement capability, users will also have the option to enable auto-adjustment control over exiting dosing pump schedules. Based on the outcome of each test result and control settings you enter, the KHD will automatically determine how much of a dose adjustment is necessary so it can maintain your KH parameter as stable as possible.

Does the KHD require a ProfiLux controller to use it?


You do not need a ProfiLux controller to use the KH Director.

To get started with testing, you would only need the KHD device and a Standalone GHL Doser. This kit is offered as a KHD Standalone Set.

GHL Doser 2.1+KH Director

Can I use a KH Director and ION Director together?


As long as you have either a Standalone Doser or ProfiLux (3 and higher) for a master device, you can conveniently integrate both devices (KHD / IOND) into one system.

Which KHD set do you recommend?

The KH Director is offered in a Standalone and EXT set. The one you should choose will depend on the equipment you currently have…

KH Director SA set
This set will include a Standalone GHL Doser 2.1. The SA doser will be the brains of the system and will be the one controlling the KH Director. We recommend this set if you do not own a GHL Standalone Doser or ProfiLux controller (3 and higher).

KH Director EXT set
This set will include a GHL Doser 2.1 EXT. This EXT doser will connect to an existing master device (Standalone GHL Doser or ProfiLux controller). The KHD in this set will also be controlled by the master device. Choose this if you already own a SA doser or ProfiLux controller (3 and higher).