One of the most powerful features in GrowVPD Pro is the ability to create automation rules that work across every brand you own. An AC Infinity controller can drive its own Cloudline fan from a live VPD reading, a Bluelab Pulse can push a pH drift alert while a Vivosun GrowHub opens a CO2 outlet during the photoperiod, and a simple Tuya smart plug can sit between any temperature sensor and a dumb oil heater for a cold-night safety net. GrowVPD Pro pulls all of it into one dashboard.

This guide walks you through everything you need to know about setting up automation rules, from basic concepts to advanced configurations.

What Are Automation Rules?

An automation rule is a simple cause-and-effect instruction: when a certain condition is met, perform an action. GrowVPD Pro checks your rules every 15 minutes in the background using Android's WorkManager, so your automation keeps running even when the app is closed.

Each rule consists of three parts:

  1. Sensor input — which device provides the data (temperature, humidity, VPD, CO2, PPFD, soil moisture)
  2. Condition — what threshold triggers the rule (e.g., VPD rises above 1.5 kPa)
  3. Action — what device should do when the condition is triggered, and what it should do when the condition is restored
Key advantage: GrowVPD Pro communicates with each brand’s cloud or controller independently, so one rule can combine a sensor and a target device from different brands (Tuya, AC Infinity, Mars Hydro, Spider Farmer, Vivosun, Bluelab, SANlight). That said, the cleanest, safest rules are usually inside one brand — an AC Infinity controller nudging its own fan, a Vivosun GrowHub opening a Vivosun outlet — because the controller is designed to run that loop. Cross-brand rules shine when you want a simple switch (a Tuya plug) to react to any sensor, or when you want notifications from a sensor that doesn’t have its own actuators (like a Bluelab Pulse).

Creating Your First Automation Rule

Open the Automation tab in GrowVPD Pro. If you have not set up a room and tent yet, you will be prompted to create one first. Once your tent is configured, tap the + Add Rule button.

Step 1: Select the Sensor Device

Choose which connected device provides the sensor data you want to monitor. This could be a standalone sensor (like a Tuya WiFi sensor) or a controller with built-in sensors (like an AC Infinity Controller 69 Pro). The app will show you which data types each device reports.

Step 2: Choose the Condition Type

Select what you want to monitor. GrowVPD Pro supports 12 condition types:

Step 3: Set the Threshold Value

Enter the value that should trigger your rule. For example, if you want to activate a fan when VPD exceeds 1.4 kPa, set the threshold to 1.4 with a "greater than" condition.

Some conditions support a range (min and max values). For example, you might want to keep humidity between 55% and 65% during flowering — set the lower threshold to 55 and the upper to 65.

Step 4: Set the Hysteresis

Hysteresis is a buffer zone that prevents your devices from rapidly cycling on and off. If your VPD threshold is 1.4 kPa with a hysteresis of 0.1, the rule triggers at 1.4 but does not restore until VPD drops below 1.3.

Tip: Always set hysteresis. Without it, a sensor reading that fluctuates around your threshold (e.g., 1.39, 1.41, 1.39, 1.41) would cause your device to switch on and off every 15 minutes. A hysteresis of 0.1 kPa for VPD or 2°C for temperature works well for most setups.

Step 5: Select the Target Device

Choose which device should respond when the condition is met. This can be any controllable device in your setup: a smart plug, an exhaust fan, a humidifier, a heater, or a grow light. The device does not need to be from the same brand as your sensor.

Step 6: Define the Actions

Set two actions:

Step 7: Optional Advanced Settings

Example Automation Rules

AC Infinity: Native VPD Loop

The single cleanest rule in a tent — same brand, built-in probe, controller in charge. Keeps your VPD inside the flowering band without the rule ever leaving AC Infinity’s own hardware loop.

Night Temperature Safety Net (Any Sensor → Tuya Plug → Dumb Heater)

A good cross-brand example. The plug is just a switch — the brains are your real sensor and GrowVPD Pro. Use whichever sensor you already trust.

Vivosun GrowHub: Daytime CO2 Enrichment

Same-brand loop again: Vivosun’s CO2 sensor trips a Vivosun outlet feeding the regulator — but only with lights on, and never longer than the hard cap. Dosing CO2 blind is dangerous; this rule is carefully fenced in.

Bluelab Pulse: pH Drift Notification (No Auto-Dose)

Root-zone pH is a place where we deliberately do not automate the actuator. A bad reading or a stuck dose can hurt plants fast. This rule watches the Pulse and pings you — you stay in the loop for any nutrient correction.

Automated Light Schedule (Mars Hydro / Spider Farmer / Vivosun LEDs)

Run your photoperiod on a stage-aware schedule, with gradual sunrise and sunset dimming so plants aren’t shocked in or out of the day.

Advanced Automation Features

Beyond the simple "if condition then action" rule, GrowVPD Pro layers in several smart features that make automation safer and more accurate. These are on by default for new tents but can be tuned per rule.

Sensor fault detection

If a sensor reading goes flat (same value to within 0.05 for several samples in a row), spikes implausibly (e.g., +10°C between readings 1 minute apart), or stops reporting for longer than its expected polling interval, the rule engine flags it as a probable fault and pauses dependent rules instead of triggering on bad data. You get a notification suggesting calibration or replacement, and rules resume automatically when the sensor recovers.

Deadband: 2-min dwell + 5-min hold

On top of hysteresis, GrowVPD Pro applies a 2-minute dwell (the condition must remain true for 2 minutes before triggering) and a 5-minute hold (the action holds for at least 5 minutes once triggered, even if the sensor briefly drops back into the safe zone). This kills the rapid-cycle problem when a sensor flickers around a threshold and protects your equipment from short on/off bursts.

Leaf temperature offset for VPD

Air temperature is not the same as leaf temperature, and VPD is what the leaf experiences. With strong direct LED light, leaves can sit 1–3°C below ambient air temp due to transpiration cooling; under HPS, they sit 1–2°C above. GrowVPD Pro lets you set a leaf temperature offset per tent and uses the corrected leaf temperature for VPD calculations and rule evaluation. This is the difference between "my chart says 1.0 kPa" and "my plants actually feel 1.0 kPa."

Night offsets (temp, RH, VPD, CO2)

Plants want different conditions during lights-off. Rather than create separate day/night rules, every condition target supports a night offset — e.g., target VPD 1.2 kPa day with a -0.3 kPa night offset means lights-off VPD target is 0.9 kPa. Offsets exist for temperature, humidity, VPD, and CO2 independently, and lights-on/lights-off is detected automatically from your light schedule.

Weighted deviation across metrics

For tents with several sensors, the engine combines deviations from target into a single weighted deviation score — e.g., temperature deviation might count more than humidity if your strain is heat-sensitive. The most actionable rule (the one that brings the deviation score down most) fires first, instead of every rule firing simultaneously and fighting each other. Weights are auto-tuned based on the active grow stage but can be overridden per tent.

Emergency override (temp spike + condensation)

Two scenarios bypass normal rule timing and force immediate action:

Normal rules resume after a 10-minute recovery window once conditions return to normal. The override is logged in the device action history for review.

Auto stage detection (3-signal voting)

GrowVPD Pro can propose a stage transition (Veg → Pre-flower → Flower → Late flower) by voting across three signals:

When at least two of the three agree, you get a notification proposing the new stage. Tap to accept, dismiss, or open settings to disable auto-detection per grow. Rule targets and offsets re-tune automatically when you accept.

Light dimming ramp (sunrise / sunset)

For supported lights (Mars Hydro iConnect, Spider Farmer, SANlight, Vivosun), GrowVPD Pro uses the device’s native ramp command to drive smooth sunrise/sunset transitions. Set lightRampSec in the stage targets (e.g., 1800 for a 30-min ramp) and the device handles the dimming locally — even if the phone is asleep or offline. For lights without native ramp, the app falls back to step-dimming through whichever channel the device supports.

Night CO2 hold

CO2 enrichment during lights-off is wasteful (plants don’t consume CO2 in the dark) and risky (without strong ventilation, levels build up). GrowVPD Pro automatically holds CO2 dosing rules during lights-off, keeping your CO2 sensor logging but never triggering the dosing valve. CO2 dosing resumes at the start of the photoperiod, with a configurable warm-up offset so your tent reaches target CO2 within a few minutes of lights-on.

Three-point band (target zones)

Beyond a single threshold, every rule supports a three-point band: a low action target, a high action target, and the safe zone in between. For example, "humidity 55–65% safe, < 55% turn on humidifier, > 65% turn on dehumidifier" is one rule with two outputs instead of two competing rules. The tent dashboard visualizes the band live and shows where current readings sit on the gauge.

Safety Features

GrowVPD Pro includes several safety mechanisms to protect your grow and your equipment:

Important: Automation rules communicate through cloud APIs, which means your devices need an active WiFi connection. If your internet goes down, rules will pause and resume automatically when connectivity returns. For mission-critical safety (like maximum temperature cutoffs), consider using your device's built-in safety features as a backup.

Room and Tent Organization

GrowVPD Pro organizes your space in a hierarchy:

  1. Room — your physical growing space (e.g., "Garage", "Spare Bedroom")
  2. Tent — individual grow tents within a room (e.g., "Veg Tent", "Flower Tent")
  3. Devices — assigned to specific tents
  4. Rules — scoped to a tent, using that tent's sensors and devices

This structure lets you run different automation profiles for each tent. Your vegetative tent might target VPD 0.8–1.0 kPa while your flowering tent targets 1.0–1.4 kPa, each with its own set of rules and devices.

Tents created in the Automation tab are automatically shared with the Grow Diary through the Equipment Profile system. When you create a new grow in the diary and assign it to a tent, the automation rules for that tent activate automatically.

Monitoring and Energy Tracking

After your rules are running, you can monitor their performance in several ways:

If a rule is triggering too frequently, that usually means your hysteresis is too small or your equipment is undersized for the space. The automation log will help you diagnose and refine your setup.