Specifications

Open Aquarium specifications define how aquarium equipment, software, and data work together. Anyone can implement them, royalty-free.

Monitoring and control

Controllers and connected equipment from any maker, working together and failing safe.

The shared vocabulary: devices, failure, and security.

Specification	Defines	Revision	Stage
Device ClassesPDF	Standard device types, from outlets and pumps to dosers and analyzers, with their telemetry, commands, faults, and optional features.	0.3	Pre‑Draft
Fail-Safe BehaviorPDF	What modules and network devices do when they lose contact, an input, or power, and how they start up.	0.2	Pre‑Draft
Security and AccessPDF	No default passwords, roles and sharing, remote access without a maker’s cloud, signed updates that are never forced, and no data sent without consent.	0.2	Pre‑Draft

How controllers, modules, devices, and apps find and talk to each other.

Specification	Defines	Revision	Stage
Module BusPDF	The wired CAN FD bus between a controller and its modules, built on Cyphal, with automatic setup and no addresses to set by hand.	0.3	Pre‑Draft
Device ProtocolPDF	Discovery, monitoring, and control on a local network over Ethernet, Wi-Fi, or Thread, with local and cloud access at the same time.	0.2	Pre‑Draft
Matter MappingPDF	How a controller appears in home apps through a Matter bridge, off until the owner turns it on, and never above its own interlocks.	0.2	Pre‑Draft

What a controller does, in formats that run the same way on any maker’s product.

Specification	Defines	Revision	Stage
AutomationPDF	Setpoints, schedules, interlocks, feed and maintenance modes, overrides, and step programs, in a format that moves between controllers.	0.2	Pre‑Draft
Lighting ProgramsPDF	Channel curves, color temperature, sun and moon, clouds and storms, acclimation, scenes, and programs you can share.	0.2	Pre‑Draft
Flow ProgramsPDF	Wave patterns, pumps from different makers kept in sync by their clocks, custom waveforms, flow-sensor control, and programs you can share.	0.2	Pre‑Draft
DosingPDF	Calibration, schedules, container tracking, missed doses never given twice, ratio dosing, and dosing adjusted from measurements.	0.2	Pre‑Draft
Water Level and Water ChangePDF	Top-off with a backup sensor and limits, automatic water changes, RO/DI systems, and leak response that keeps heaters covered.	0.2	Pre‑Draft
Water TestingPDF	Analyzer schedules, reagents and waste, results screened before use, and corrections from laboratory results that a person confirms.	0.2	Pre‑Draft
Alarms and NotificationsPDF	Severity for every fault, a buzzer that works without a network, escalation until someone acknowledges, and delivery without a maker’s cloud.	0.2	Pre‑Draft

Electrical interfaces between controllers, modules, probes, and power. See how they connect

Specification	Defines	Revision	Stage
Probe InterfacePDF	Probe ports, galvanic isolation, and input characteristics, with one calibration procedure for each probe type on every product.	0.3	Pre‑Draft
Power ModulePDF	Switched mains outlets: a declared state for each without power, monitoring that catches a welded relay, a backup thermostat, and protection that never depends on firmware.	0.2	Pre‑Draft

One record of the whole aquarium, used by every area: its systems, equipment, water, livestock, and care.

Specification	Defines	Revision	Stage
Data ModelPDF	Systems, equipment, measurements, lab results, events, livestock, target ranges, tasks, calibrations, and history, every value with an explicit unit.	0.3	Pre‑Draft

Each one fills up stage by stage. Approval needs more than agreement: it needs working products from more than one organization.

Proposal

An idea with a written rationale. Optional for small changes.
Pre‑Draft

A candidate document, submitted for consideration and open for comment.

Every specification is here today.
Draft

Adopted by consensus as the basis for all further work.
Approved

Stable enough to build products against, after a 30-day public review, two independent implementations that work together, and published conformance materials.

The same layout, from the first Pre‑Draft on.

The five principles
How it meets openness, interoperability, local control, safety, and sustainability.
Requirements you can test
Numbered sections with MUST, SHOULD, and MAY, and a test procedure wherever behavior can be tested.
Machine-readable files
Schemas, registries, examples, and test vectors beside the text, under Apache-2.0.
A royalty-free license
The Community Specification License 1.0, with patent commitments from every contributor.
A revision history and a PDF
Every change recorded, and every revision typeset as a PDF with its stage on every page.
Open issues
What is still undecided, listed in an appendix, so you know where your comments count.

Comment on a draft with an issue, or read how to propose a new specification.