Dosing · Reasoning · Community

OpenDose: the open reef dosing method.

A complete method for dosing, testing and ICP corrections, run through the AI chat you already use. And it doesn't stop at dosing:

  • Your own OpenDose app. Your AI builds it for your tank from our prompt, to monitor and manage everything.
  • Community data. Learn from every tank running OpenDose, and add yours.
  • AI reasoning for anything. Ask about any part of your reef, not just dosing.
Your AI chat Example
My ICP came back. Here are the results.
Potassium has drifted down since your last test, and you switched salt in between. That may be the salt, not consumption. Medium riskRaise Bottle A by 0.5 ml a day, then retest in 2 weeks. Want me to log this change?

A method, not a recipe.

Fixed methods hand you a product list, a lab and a spreadsheet. OpenDose hands you the reasoning. Your AI weighs your whole tank, suggests small changes, and you decide.

Any product

Raw chemicals or any brand. Your AI just needs to know what's in it.

Any ICP lab

Pick the lab you like. Your AI tracks which lab each result came from.

Any AI

ChatGPT, Claude or another. Add the Core file, or connect it to OpenDose.

Ebb and flow

Small changes, judged by the next test. A 10% water change once a month handles the rest.

Start in about two minutes.

No software to install, no spreadsheets, no new app to learn. You use the AI you already have.

  1. 1

    Open your AI

    ChatGPT, Claude, Gemini, whichever you use. Start a new project or chat just for your tank.

  2. 2

    Add one small file

    Drop the OpenDose Core into that project. It's just text that guides your AI's thinking and reminds it to share what your tank learns.

  3. 3

    Say "let's start"

    Your AI asks how many tanks you run, then about each one, one question at a time. It hands you a tank file for each to save in the project. That's the setup done.

Step-by-step setup for ChatGPT, Claude and Gemini

After that, just talk to it.

Paste in a test result or an ICP and ask what to do. It explains its thinking, gives a risk level, and waits for your OK. It keeps your tank file up to date and lets you know when the Core has an update.

  • Works with the AI you already pay for, or a free one
  • Your tank file stays with you, not on our site
  • No data entry chores, it only asks when it needs to
  • Want more? Build your own app later. Totally optional.

Why not just ask an AI?

You can, but without structure it's easy to go in circles. The Core gives your AI a path to follow, and your tank file gives it your whole tank to reason from.

Just asking an AIWith OpenDose
Starts from scratch every chatKnows your whole tank, every time
Generic answersReasons from your dosing, salt, feeding and history
Easy to wander and get lostA clear path: set up, test, decide, log
No sense of riskEvery suggestion comes with a risk level
Learns nothing from other tanksDraws on what the whole community has learned

Set up your dosing, your way.

Your AI helps you build a dosing setup that fits your tank, from scratch or from what you already run.

Dosing pumps

Plan heads, schedules and safety caps for any doser. Small doses through the day.

By hand

No pumps? Get a simple daily routine sized to what your tank actually uses.

Mix your own

Make your own solutions from raw chemicals instead of store-bought bottles. Your AI works out recipes, strengths and what can share a bottle.

Balanced trace mixes

The heart of OpenDose. Each trace bottle is mixed in the ratios your tank actually uses, so one small daily dose holds every element in it steady. After each ICP, your AI rebalances the next batch instead of chasing big corrections.

Prefer store-bought? That works too. Any brand, or a mix of both.

Dosing plan

Example tank, 189 L
HeadPer dayWhen
Alkalinity (2-part)13 ml8 small doses
Calcium (2-part)12 ml2 doses
Magnesium4 mlMorning
Kalkwasser770 mlOvernight
Trace bottles A, B, C3 ml eachMorning
Nitrate, phosphate1 ml, 5 mlSeparate heads

Every head has a max per dose and per day. Your AI never suggests past it.

Build your own OpenDose app.

Our App Creator prompt has your own AI build an OpenDose app made for your tank. Answer a few questions and it's 99% of the way there.

  • Connects to your dosers, monitors and lights
  • Logs tests, ICPs and every change in one place
  • Reminds you when tests and bottle remakes are due
  • Your AI reads it, you stay in control
Get the app prompt
OpenDose · My reefExample

Alkalinity

9.0 dKH

Calcium

440 ppm

Magnesium

1440 ppm

Temperature

77.3 °F

Nitrate

10.4 ppm

Phosphate

0.08 ppm

Due soon

Magnesium test

Remake Bottle C (iron)

Three layers of knowledge

Your AI reads all three, so it knows the method, what other tanks have learned, and everything about yours.

The Core

The method itself

Safety, risk levels and reasoning rules. Keep your own copy, so you never lose it.

Community

What every tank has learned

Shared tank data, mix reports and lessons, growing every week.

Your tank file

Everything about your reef

Private, and it stays with you. Only tank data is ever shared, and only if you choose.

Free. Always free.

OpenDose gets better with every tank that joins. One tank can't tell you why something happened. Hundreds of tanks, recorded the same way, can. Be part of building it: share what you learn, vote on what goes into the Core, and talk it through on Discord.

Tell OpenDose. Wish the app did something, or want something changed? Just tell your AI. It sends your idea to OpenDose, where the community votes on what gets built next.

Want to help keep it running?

Everything stays free. Supporters chip in to cover hosting and testing, by donation.

Become a supporter

Open and flexible means you're in charge, and responsible.

OpenDose is not a standardized, proven recipe. It carries more risk than fixed methods. One wrong decimal can seriously harm a reef tank. Always check the concentration and math behind a dose, and change things slowly.

Read the full disclaimer