Description

The CoralVue HYDROS Control X4 Starter Pack is the easiest way into one of the most thoughtfully engineered aquarium controller platforms available. Unlike controller systems that require multiple add-on modules before they’re genuinely useful, the Control X4 handles temperature, pH, ORP, water level monitoring and small pump control out of a single unit — with no additional purchases required to get a fully functional system running on day one.
Designed, assembled and supported entirely in the USA, the HYDROS ecosystem was built by reef keepers who understood the practical realities of running a saltwater system in a living space — noise, moisture, corrosive salt spray, the consequences of a single point of failure and the frustration of systems that require technical expertise to configure.

IP65-rated industrial enclosure — built for the reef environment
Most aquarium controllers are housed in plastic enclosures that weren’t designed with salt spray in mind. The HYDROS Control X4 uses an IP65-rated enclosure — dust-proof and splash-resistant — with aircraft-grade connectors that maintain secure, reliable connections even in the humid, corrosive environment directly above or beside an active reef system. The unit looks like industrial equipment because it is industrial equipment, applied to aquarium use.
Dual-core 32-bit processor — decisions made locally, instantly
The Control X4 runs on a fast dual-core 32-bit processor, and all control decisions — turning equipment on or off in response to parameter changes, triggering alerts, executing schedules — are made within the device itself. This means the controller responds in real time without depending on an internet connection. Local WiFi control works entirely without cloud access; the HYDROS Cloud is an additional layer for remote access, not a dependency.
Internal health monitoring tracks voltages, currents, CPU status and the internal temperature of the device itself, reporting any anomaly before it can become a problem.
Sense Ports — a new concept in parameter measurement
The four Sense Ports on the Control X4 represent a genuinely new approach to aquarium monitoring. Unlike dedicated ports that accept only one type of sensor, each Sense Port is a universal input that can accept data from temperature sensors, water level sensors, optical sensors, leak detectors and other accessories — the same port works for different tasks depending on what’s connected. This means the sensor complement of the system can be reconfigured as needs change without adding hardware.
Probe Ports with digital galvanic isolation
The two Probe Ports accept pH or ORP probes, and the signal conditioning behind them is unusually well-engineered for an aquarium product. Each port uses ultra-high-quality input circuitry specifically designed for electrochemical probes, with digital galvanic isolation that prevents interference from motors and pumps connected elsewhere in the system. The isolation converts the probe signal to a digital domain before it crosses into the control circuitry — preserving accuracy even in electrically noisy sump environments.
Drive Ports — powered outputs with current monitoring
Two Drive Ports provide switched 12V DC power for small motors, pumps, ATO pumps, solenoids and other accessories. Each port’s current draw is monitored continuously — if a connected device stops drawing current (pump failure) or draws significantly more than expected (blocked impeller), the Controller detects the anomaly and sends an immediate notification. This turns every connected device into a monitored device.
0-10V I/O — compatibility beyond the HYDROS ecosystem
Two 0-10V input/output ports allow the Control X4 to send and receive commands from variable speed pumps, push buttons, float switches and — importantly — equipment from other brands. Legacy automation systems can provide input via these ports, and variable speed pumps from non-HYDROS manufacturers can be controlled through them.
HYDROS Command Bus — no single point of failure
The Command Bus ports connect multiple HYDROS devices together, enabling them to share power and communicate in a redundant network where no single device is a critical dependency. Every HYDROS product in a connected system has its own CPU and can operate independently — if any individual device loses communication, the others continue functioning autonomously. This distributed architecture is a fundamental design difference from systems where all control passes through a single central controller.
WiFi device control — up to 8 additional outlets
Through the HYDROS app, the Control X4 can create rules and schedules to control up to 8 HYDROS WiFi Smart Outlets and 4-outlet WiFi Power Strips — turning lights, skimmers, heaters, pumps, UV sterilizers and other equipment on and off based on time, parameter readings or manual commands, without requiring any physical wiring between the device and the outlet.
The HYDROS app — aquarium control without programming
Setup and operation require no coding, no programming language and no technical background. The app uses tap, drag, press and flick interactions to configure schedules, set parameter thresholds, create automation rules and manage notifications. The same interface works for a first-time controller user and an experienced reefer building a complex multi-device system.
What’s in the Starter Pack
The kit ships with everything needed to start monitoring and controlling a real aquarium immediately — Control X4 unit, temperature sensor, pH probe with calibration solutions, Command Bus cable and all necessary hardware. Nothing additional is required for basic operation.
Specifications:

Processor: dual-core 32-bit
Sense Ports: 4 (universal input — temperature, level, leak, optical)
Probe Ports: 2 (pH / ORP, digitally galvanically isolated)
Drive Ports: 2 (switched 12V DC, current monitored, up to 1A each / 1.5A total)
0-10V I/O Ports: 2
Command Bus Ports: 2
WiFi device control: up to 8 devices
Enclosure rating: IP65
Connectivity: WiFi (local) + HYDROS Cloud (remote)
Dimensions: 7.8″ L × 3.6″ W × 2.5″ H
Made in: USA

In the box: HYDROS Control X4 unit, temperature sensor, pH probe, pH calibration solutions, Command Bus cable, power supply