Summary #

Precision is the defining feature of the GHL Doser. This guide covers the essential setup steps, from mandatory calibration and container management to defining the system logic and configuring specific dosing schedules or continuous operation.

For device-specific instruction manuals, see the Downloads section below.

Applies to #

• GHL Doser 2 / Maxi / 2.2 Maxi Series (incl. Industrial Line / IL)
• GHL Doser 3 / 3 Maxi Series (incl. Industrial Line / IL)
• Compatible controller:
  • ProfiLux 4 Series (incl. Industrial Line / IL)
  • ProfiLux 3 Series
• Software:
  • GHL Connect (App, Webinterface, myGHL)
  • GHL Control Center

Prerequisites #

• Calibration Tool: A precise measuring cylinder (e.g., 50ml or 100ml) or a precision scale (measuring in grams, as 1ml of water equals approximately 1g).
• Software Access: GHL Connect app, GHL Control Center, or myGHL.
• Hardware connection: Connect the Doser to a power outlet using the supplied 24V power supply and connect all tubing. On each pump head, the left connection is always the intake (suction side) and the right is the outlet.

Connecting to GHL Connect or GHL Control Center #

After powering on the Doser, connect to it via GHL Connect or GHL Control Center to proceed with the initial configuration.

On first startup, the Doser SA creates a WiFi access point — connect to it using GHL Connect to configure a permanent network connection. Alternatively, connect via USB. See the Network (LAN & WiFi) – Setup Guide and GHL Connect & GHL Control Center – Installation & Setup for details.

Step 1: Initial Settings (SA Models) #

Open General to access device-wide settings. Start with the Operation Mode, as it determines how the Doser is used and which of the following steps apply.

Operation Mode #

Determines whether the Doser operates independently or as an extension of another device.

• Standalone / Master: The Doser operates on its own schedule or acts as master for other EXT Dosers. In this mode, the Doser must not be connected via PAB to a ProfiLux or another Doser SA.
• Extension / EXT: The Doser acts as a PAB extension device and is controlled by a ProfiLux 3/4 or another Doser SA as master.

Time & Date #

Set the correct time and date. Enable NTP for automatic synchronization when connected to a network. Also set the correct timezone and enable Change from winter to summer time if automatic daylight saving time adjustment is needed.

Alarm (Buzzer) #

Configure when the buzzer sounds: Off, Always, or At set time (with a configurable start and end time).

GHL Logo Illumination #

Set the brightness and mode of the GHL logo LED — Standard (with blinking), Standard without blinking, Off, or a constant color. See the GHL Logo – Status Indicator article for the meaning of each color and blink pattern.

Temperature Sensor #

In GHL Control Center, the temperature sensor is configured directly on the General page — enable or disable it and set the unit (°C / °F). In GHL Connect, the temperature sensor has its own dedicated sensor page.

Step 2: PAB Connection & Configuration (EXT Models) #

If you are using an Extension (EXT) unit, or have set your Doser SA to Extension mode in the General settings above, it must be linked and configured to your master device before it can be used.

1. Physical Connection & Assignment #

1. Connect the EXT Doser to the Master device using a PAB cable. Use only the dedicated PAB ports; never plug PAB cables into LAN/Ethernet ports.
2. In GHL Control Center: Go to the System page and click Assign devices.
3. In GHL Connect: Go to the System page, select Assign and configure connected PAB devices, and then click Assign devices.

2. Pump Numbering & Upgrade Kit Settings #

To avoid conflicts and ensure the correct motor control:

• Accessing Configuration:
  • In GHL Control Center: Go to the System page, select/highlight the Doser in the device tree, and click Configuration.
  • In GHL Connect: Go to the System page, select Assign and configure connected PAB devices, and click the gear icon next to the respective PAB device.
• Start numbering: Within the configuration menu, set the Start numbering. If your Master unit already uses Pumps 1–4, set your Extension unit to start at 5.
• Doser 3 Upgrade Kit: If you upgraded a Doser 2 with Doser 3 pump heads, ensure firmware v1.55+ is installed. In the same configuration menu, check the box “Doser 3 pump heads upgrade present” and click save the changes.

Step 3: Mandatory Priming & Calibration #

Before any dosing task can be performed, the pump must be calibrated. This allows the software to calculate the exact relationship between motor RPM and actual fluid displacement at a specific speed.

1. Setting Pump Speed #

First, define the Max. speed (0-3) in the pump settings.

• 0: Slowest
• 3: Fastest (Note: Speed 3 cannot be used for Continuous Mode).

Important: If you change the speed level later, you must repeat the calibration process.

2. Priming the Lines #

Ensure the dosing tube is completely filled with liquid and contains no air bubbles. Use the Manual dosing button on the device or in the software to run the pump until the fluid reaches the end of the tube.

3. Running Calibration to determine “Max. flow” #

Click the Calibrate pump button. The pump will run for exactly one minute.

• Collect the fluid in your cylinder or weigh it on your scale.
• Enter the resulting volume into the Max. flow field and save. This value represents the maximum flow rate at your chosen speed.

4. Defining the Desired Flow #

Once the Max. flow is saved, you can set the Desired flow. This is the specific volume in milliliters per minute (ml/min) you wish the pump to deliver during constant operation.

• The Desired flow cannot exceed the Max. flow determined during calibration.

Tips for maximum accuracy #

• Match speed to precision needs: Use a slower speed for small, high-precision doses (e.g., trace elements) and a faster speed for larger amounts where absolute precision matters less. Calibration is only valid for the exact speed it was performed at — if you change the speed later, you must repeat the calibration.
• Keep tubing short: Keep the tubing between container and pump as short as possible — ideally not exceeding 60cm (2ft). The larger the fluid volume held inside the tubing, the less accurate the dosing becomes, so some applications may require longer runs despite the reduced precision.
• Use the smallest suitable diameter: For the same reason as tubing length — less fluid volume held inside the line — choose the smallest inner tubing diameter that still works reliably for your application.
• Avoid large height differences: Keep the dosing container, pump, and aquarium at similar heights where possible. Large height differences can affect flow consistency.

Step 4: Container & Fill Level Management #

Avoid running your pumps dry by configuring container tracking. This section defines how the Doser monitors your fluid supply.

• Fill Direction: Set to Container will be emptied for standard dosing or Container will be filled for waste collection.
• Scaling: Choose Small cont. (up to 30,000ml) for ml precision or Large cont. (up to 3,000L) for bulk storage.
  Note: Large containers are less precise for small ml increments.
• Capacity & Threshold: Enter the Capacity of your container. Set a Minimum/Maximum threshold for alerts.
• Alarm vs. Warning: Toggle Alarm when below min. for an active alert; otherwise, a silent warning is issued.
• Maintenance Buttons: Use Refill container or Empty container to reset the software counter after refilling your jugs.

Note: Enable Switch off level monitoring to deactivate level monitoring completely, including alarms and warnings.

Step 5: System Logic – “Pump reacts to” #

This setting determines what triggers the pump to move. It is the bridge between the hardware and the programming.

• On ProfiLux 3/4 (EXT Dosers):
  • Select Dosing schedule below for standard schedules or continuous mode.
  • Select Switch channel index to trigger dosing via a specific logic-controlled switch channel (e.g., managed by Programmable Logic).
• On Doser Standalone:
  • Select Dosing schedule below for standard schedules or continuous mode.
  • Select Level control to allow the pump to react directly to sensor inputs (e.g., for ATO or Water Change functions).

Step 6: Operational Modes: Schedules & Continuous Dosing #

Once the logic is set to Dosing schedule below, you can configure how the fluid is delivered.

Daymode Selection #

Regardless of whether you choose a Schedule or Continuous operation, you must define the Daymode to determine when the pump is active:

• At special weekdays: Select specific days of the week.
• In day-intervals: Set Repeat every (e.g., every 2 days) and Starting in (delay from today).

Option A: Dosing Schedule #

Used for periodic supplements (e.g., KH, Calcium, Trace elements).

• Automatic times: Define the Dosings per day and the Rate per dosing. GHL automatically distributes these events. You can toggle Always dose at that time for fixed intervals.
• Individual times: Click New (+) to manually add events. Define the Start time and Rate / dosing [ml] for each.

Note: The Average daily dosing amount field displays the total calculated daily volume based on your schedule.

Option B: Continuous Mode #

Used for constant delivery (e.g., Calcium reactors).

• Pre-configuration: You must set your Max. speed, Max. flow (Calibration), and Desired flow before activating this mode. Once Continuous Mode is enabled, these fields become grayed out and cannot be edited until the pump is stopped or switched back to another mode.
• Speed Restriction: Continuous Mode is only available for Speeds 0, 1, and 2. If Speed 3 is selected, the Continuous Mode option will be disabled/grayed out to prevent motor damage.
• Operation: The Doser uses the Max. flow and Desired flow values to calculate the precise motor RPM required for a steady, 24/7 stream.

Step 7: Monitoring and Recording #

Enable Record dosings in the pump settings to track performance. This allows you to visualize consumption trends and verify that the system is operating as expected. To view these logs:

• GHL Connect: While on the settings page for the specific pump, switch to the History tab at the top.
• GHL Control Center: Navigate to Probe/sensor controls in the left menu and select Measurement data.

Downloads #

• GHL Doser 2 Manual
• GHL Doser 3 Manual
• GHL Doser Maxi Manual
• GHL Doser 2.2 Maxi Manual