A fish tank controller for Raspberry PI - in the implementation phase
By using small functional blocks, this software can build the controller functions for your fish tank in a highly modular way. The result is minimal hardware requirements and a UI reduced to your desired functions, whether a simple light dimmer or a complex setup with redundant temperature sensors, many lights, a pH controller and dosers. Based on a Raspberry Pi (Model zero or better), you can get a versatile solution, including diagrams, email or Telegram alarms, multi-channel dimmers, etc., for a competitive price. Some experience with hardware setup is required. We're working hard to reduce this part, e.g. the common TC420 LED controller can be integrated, thus eliminating the need for re-cabling or getting new power drivers (MOSFET). The software can be used with RoboTank or Leviathan boards, sold in the U.S (some subfunctions not supported yet).
On the technical side - for those who like to understand the inner workings or to contribute: The project is based on Python/Flask as the backend, plus Vuetify as the reactive frontend. The Raspberry runs "headless", meaning your mobile, tablet, or PC will display the user interface.
To explain the building blocks, let's start with a simple temperature controller:
You select an analog input node (reading values from a temperature sensor) and connect it to a threshold node (switching on/off depending on the reading), which then is connected to a relay output node (writing to a configurable driver). That's all.
Later, for improved reliability, you might want to have redundant sensors; you would simply add another input node reading a 2nd sensor, plus an averaging node to combine both readings. Finally, you would reconnect your threshold node to use the average instead of the initial input.
AquaPi is designed to work entirely offline, with no cloud! The WiFi network is required to allow the user interface on your mobile or PC (in your browser), but the communication stays in your WiFi zone unless you decide to expose it through VPN or similar.
What is working so far?
The backend is complete to allow running my :-) aquarium with dimmed light, temperature and pH/CO2. The UI is basically working for monitoring, including graphical charts. Drivers for relays, onboard PWM, TC420, temperature sensor DS1820 and ADC AD1115 (pH probe!) are working; more to follow. The configuration of controller blocks has no user interface yet; you need to edit the (simple!) Python source to define the nodes described above.
What is needed?
- More drivers for I²C chips and WiFi devices (e.g. Shelly) must be implemented.
- The initial UI, based on Flask & Jinja, is being converted to a modern SPA using Vuetify.
- Frontend and backend need translations.
- Reporting functions in various ways (email/Telegram alerts, logging page).
- Documentation. Testing. Translation.
- Packaging and installation (ATM this project has no build step and probably will never need it, meaning you can modify the software on your target system.)
If you are interested in contributing in any form, you are welcome! Please leave a note in Discussion or Issues. If you don't want to contribute but have an idea of a "killer feature" that would make you replace your current solution ;-) let's talk about it in Discussions too. BTW, German is my native language; feel free to use it here.
To start, clone the repository to e.g. ~/aquaPI on your Linux system, then source ". aquaPI/init". This step will initialize Python and all dependencies. It will also explain how to run the development instance of aquaPi.
Windows is not actively supported as a development environment (currently, it seems to work) - in lack of a Windows PC fixing Windows-only issues has no priority. The target system is limited to Raspberry OS anyways. My development environment is Manjaro Linux. All drivers support a simulation mode, so no Raspberry is needed for development.
Markus Kuhn, 2023-03-29