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Apex Programmer

Generate, simulate, and de-risk Neptune Apex programs — quick code, logic-block builder, safety analysis, and failure simulation.

Heads up: Generated Apex code is educational and must be tested before use. Incorrect Apex programming can flood your home, overheat or chill your tank, overdose chemicals, shut down life support, or harm livestock. Always confirm sensor OPEN/CLOSED states manually in Fusion before relying on automation.

Generate Apex code for reef equipment, understand what it does, and catch risky automation mistakes before you paste it into Fusion. Built around common Apex programming patterns reefers use for failsafes, feed modes, and emergency shutoffs.

My saved setups 0

No saved setups yet. After you generate code in the Quick Generator, click Save setup to keep it in your browser for next time.

Step 1 Choose your path

Step 2 Pick your scenario

Starting points

What are you trying to automate?

Pick the closest match — we'll jump you to the right tool with sensible defaults already filled in. If you'd rather drive, scroll past and use the tabs below.

Or build a whole-tank setup or safety mode

Step 3 Configure your setup

Make code, fast

Pick your gear, pick a scenario, hit Generate. You get copy-ready Apex code with line-by-line explanations and safety checks.

Equipment Type ? Outlet Name ?

Scenarios ?

More options probes, sensors, virtual outlets — only the ones your scenarios need are shown

Temperature Probe Name ? pH Probe Name ? ORP Probe Name ? Return Pump Outlet ? Maintenance Virtual Outlet ? Leak Sensor Name ? Leak Trigger State ? Alarm Output Name ? Feed Mode ?

Step 4 Review your Apex setup

Your generated Apex code will appear here.

Pick equipment + a scenario above. Code generates automatically as you change fields.

Build it block by block

Stack logic blocks in the order Apex will run them. Top to bottom — and the last matching line wins.

Set up a repeating cycle

OSC is how Apex runs anything on a loop — dosing, kalk stirring, alternating powerheads. The format is OSC initial_off / on_time / off_time Then ON.

OSC Preset (optional)

Initial Delay (mm:ss) ON Duration (mm:ss) OFF Duration (mm:ss) Action

Plan your feed mode

Tell us what should pause when you hit feed in Fusion. The number after FeedA is how many minutes the outlet keeps reacting after feed mode ends.

Feed Mode Feed Duration Note (informational)

Equipment Behavior Return Pump OFF Skimmer OFF (with 5 min restart) Wavemakers OFF UV OFF ATO OFF Dosing OFF Lights affected

Build a virtual outlet

Virtual outlets are software-only switches you flip in Fusion to trigger groups of behaviors at once — Maintenance, Vacation, Dino Mode, that kind of thing.

Virtual Outlet

Check my code

Paste your Apex code. We'll flag the dangerous stuff, the slightly-sketchy stuff, and suggest safer ways to write it.

Equipment Type (helps analysis)

Generate or paste code to run a safety check.

Paste any Apex code in the box above and we'll explain it line by line + flag risky patterns.

Step 5 Test before using

Test your setup before using it

Paste your code, pick a worst-case scenario — heater stuck on, ATO stuck open, leak hits — and we'll trace what your code does line by line and where the gaps are.

Scenario

Simulation results will appear here.

Paste your code and pick a scenario. We'll show what the code does line by line and where the gaps are.

Translate this code

Paste any Apex code and we'll tell you what each line actually does, in plain English.

Plain-English explanations will appear here.

Paste Apex code from a forum, an old config, or anywhere else and we'll translate every line.

Browse battle-tested presets

Starting points that other reefers have run on real tanks. Always confirm sensor states and outlet names match yours before pasting.