Mars Hydro Controller 43 Smart Environmental Controller

The Mars Hydro Controller 43 is a centralized environmental monitoring and lighting control system designed for indoor gardens, grow rooms, greenhouses, and other controlled horticultural environments. It combines real time temperature and humidity monitoring with programmable grow light control, VPD tracking, remote access through the MarsPro App, and optional PPFD and CO₂ sensing.

Compatible Mars Hydro grow lights can be connected directly through RJ12 communication cables, allowing the Controller 43 to synchronize and manage up to 40 lights in series. Growers can adjust light intensity, create daily operating schedules, program sunrise and sunset transitions, and monitor environmental conditions from one interface.

When equipped with the PAR and CO₂ sensors, the Controller 43 expands beyond basic climate monitoring to display PPFD and CO₂ concentration alongside temperature, humidity, and calculated VPD.

• Monitors temperature, humidity, VPD, and optionally PPFD and CO₂
• Controls up to 40 compatible grow lights via RJ12
• Remote monitoring and control through the MarsPro App
• Programmable dimming, timers, and sunrise/sunset transitions

Temperature and Humidity Monitoring

The included 3 in 1 sensor continuously monitors the growing environment and supplies temperature and humidity information directly to the Controller 43.

The controller supports a humidity monitoring range of approximately 5% to 95% RH with accuracy rated at ±3%. Temperature measurement extends from approximately 20°C below zero to 100°C, with a listed accuracy of approximately ±0.75°C.

VPD Monitoring

The Controller 43 uses temperature and humidity data to calculate Vapor Pressure Deficit, or VPD. VPD provides a more useful picture of the relationship between air temperature and moisture than either temperature or humidity alone.

Displaying VPD alongside the primary environmental readings allows growers to monitor how changes in temperature or relative humidity are affecting the overall growing environment without manually calculating the value.

Optional PPFD Monitoring

Adding the PAR sensor allows the Controller 43 to measure PPFD directly within the growing area. Mars Hydro lists a PPFD measurement range of approximately 0 to 4,000 µmol/m²/s and a spectral response covering approximately 400 to 700 nm.

This allows growers to monitor actual light intensity at the plant canopy instead of relying only on dimmer percentages or manufacturer output specifications. The home screen is designed to display PPFD alongside temperature, humidity, and CO₂ when the appropriate sensors are connected.

Optional CO₂ Monitoring

The optional CO₂ sensor expands the system into a more complete environmental monitoring platform. Mars Hydro lists a CO₂ measurement range of approximately 0 to 5,000 ppm, with sensor accuracy rated at approximately ±50 ppm plus 5% of the reading.

CO₂ information is displayed directly on the Controller 43 and can also be accessed through the MarsPro App, providing a convenient way to view concentration alongside light intensity, temperature, humidity, and VPD.

Control Up to 40 Grow Lights

The Controller 43 can synchronize as many as 40 compatible grow lights in series. Lights connect through the controller's RJ12 system, allowing a group of fixtures to operate from common schedules and dimming settings rather than requiring each light to be adjusted individually.

This makes the Controller 43 suitable for both individual grow tents and larger rooms using multiple compatible fixtures.

Works With Bluetooth and Non Bluetooth Lights

Compatible Mars Hydro lighting does not necessarily need built in Bluetooth to use the Controller 43. Grow lights can be connected through the controller and compatible dimming hardware using RJ12 communication cables.

Once connected, lighting intensity and scheduling can be managed through the physical controller or MarsPro App.

Programmable Light Dimming

The Controller 43 provides centralized adjustment of compatible LED grow light output. Instead of manually turning dimmer knobs on individual fixtures, growers can set lighting intensity directly through the controller.

This allows intensity to be changed as plants progress through propagation, vegetative growth, flowering, or other stages with different light requirements.

Sunrise and Sunset Simulation

Lighting schedules can include gradual sunrise and sunset transitions. Rather than switching immediately from off to full intensity, the controller can progressively increase output at the beginning of the programmed photoperiod and reduce output before lights turn off.

This provides smoother daily transitions while also automating a task that would otherwise require manual dimming.

Automatic Light Protection

The Controller 43 includes automated temperature based lighting protection. When configured, the controller can reduce lighting output automatically if the temperature reaches a preset threshold, and an automatic shutoff function can also turn lights off when the selected temperature limit is exceeded.

This gives growers another layer of protection against excessive heat conditions when using compatible connected lights.

Environmental Alerts

Users can configure warning thresholds for key environmental readings, including temperature, humidity, CO₂, and PPFD.

When monitored conditions move outside the selected range, the Controller 43 can identify the abnormal condition so the grower can respond before environmental stress becomes more significant.

MarsPro App Remote Control

Connecting the Controller 43 to the MarsPro App adds remote monitoring and control. Through the app, users can access environmental information and manage compatible connected equipment without standing directly in front of the controller.

The app supports setup on both Android and iOS devices and shows remote access to temperature, humidity, VPD, CO₂, PPFD, dimming, and timing functions.

iHub 4AC Integration

The Controller 43 can also work with the optional Mars Hydro iHub 4AC power strip. With the iHub connected, the system can control compatible supplemental UV, IR, red, and blue lighting bars, including on/off control, multi timing schedules, cycle timing, UV timing, and IR timing.

The iHub 4AC is sold separately.

Multi Timing and Cycle Timing

Multi timing allows several activation periods to be programmed within the same day, useful for equipment that should operate during specific portions of the photoperiod rather than continuously.

Cycle timing repeatedly switches a connected output on and off according to a selected schedule. Instead of specifying only one daily start and stop time, users can define an activation duration and recurring cycle — useful for supplemental light bars or other compatible controlled devices that need intermittent operation.

Compact Controller Design

The Controller 43 measures approximately 6.22" x 4.25" x 1.45", making it compact enough for mounting inside or near a grow space without occupying significant wall area. An installation rail is supplied for mounting.

The controller operates from a 12V DC power supply and consumes approximately 4W.

Local Controls

The physical Controller 43 includes its own screen and directional buttons, allowing major functions to be accessed without relying exclusively on a smartphone. Controls provide navigation for device status, light groups, iHub groups, environmental settings, alarm information, and system settings.

This keeps essential control available locally even when users prefer not to manage the system through the app.

What's Included

The exact package depends on the selected configuration.

Standard Controller Package:

• Mars Hydro Controller 43
• Temperature, Humidity and Light 3 in 1 Sensor
• Installation rail
• RJ12 communication cable
• Power supply

Controller With PAR and CO₂ Sensors:

• Mars Hydro Controller 43
• Temperature, Humidity and Light 3 in 1 Sensor
• PAR Sensor
• CO₂ Sensor
• PPFD Adapter
• RJ12 T Shape Splitter
• 3 x 3m RJ12 Cables
• Installation rail
• Power supply