17. Applications & Implications¶
This week was a milestone class week, where work on the final project officially begins, something that I’m super stoked to be finally working on. Although I’ve been directing much of my previous 16 weeks worth of work towards my Final Project, an Assistive Aquaponics Fish Tank, this week I sat down to answer some questions about my project, flattening out any planning left to do, and leaving an outline to complete the project upon. (May 19)
10-12 minutes
What will it do?¶
Due to my current lack of schedule flexibility with being a high school student, I’ve always found the practice of gardening hard to keep up with, but have always had an interest in pursuing a garden despite that, as discussed on my Final Project page. I’m looking to create an “Assistive Aquaponics Fish Tank”, a sustainable way to grow small herbs and plants inside with little required time, while also eliminating much of the guesswork from the gardening process, hopefully providing a super time-efficient way to keep up with a garden, on a tight schedule. This assistive nature of the project, as opposed to complete automation, is in hopes of retaining the aspects of owning a garden I’m looking for, or at least as much as I can in a time-efficient manner. My Final Project tank will make use of Aquaponics to create this more time-efficient product, converting the care of my garden, into the simple task of feeding fish, a chore already done in my household. “Aquaponics is a system of producing food that combines aquaculture (raising fish, snails, or prawns) and hydroponics (growing plants in water). It can be an elegant closed system whereby the fish produce waste which, in turn, circulates to feed the plants which, in turn, purify the water for the next school of aquatic generations” (The Evolution of “Ponics” in Organic).
Who has done what beforehand?¶
During the original planning of my final project concept in my week 1 class, I found a handful of links to Assistive/Automated x Gardening themed projects, with some influential ones included below …
- Gardening + Arduino
- Garduino
- DIY Home Assistant Garden Automation System
- Raspberry Pi Powered IOT Garden
- Advanced Irrigation System
… however, as discussed at the start of my Final Project page, this original garden project concept of mine evolved into the assistive aquaponics tank described above. Aquaponics, although a new field to me personally, is not new to the Fab Academy, with the notable Aquapioners project from the 2016 cycle of the class stand out.
What will you design?¶
As mentioned at the top of this page, I’ve been directing much of my previous 16 weeks’ worth of work towards my Final Project, and already have some elements sorted out, attached below…
| Week | Tool/Practice | Product | Link to Compleation |
|---|---|---|---|
| 6 | Electronics Design | Tank Main Board | ✔️ First Board Iteration |
| 7 | CNC Milling | Aquaponics Tank Plywood Structure | ✔️ Plywood Tank Structure |
| 11 | Inputs | Temp/Humidity Sensor | ✔️ Temp/Humidity Board |
| 13 | Outputs | LCD | ✔️ LCD Breakout Board |
| 14 | Networking & Communication | LCD Interface & Tank System Communication | ✔️ LCD Interface & Communications |
Following these bits, the acrylic tank itself will be designed by me, along with mounting from all electronics, a power breakout board, the project’s plant box & water pumping system, and any other smaller bits required by the project. The only upcoming part of my project that will not be designed by being is the board that attaches directly to the glass pH probe used by my tank, however, my system will have a pH sensor board interfaced to this board, reading the sensors analog values with an ATTiny 412.
Bill of Materials¶
What materials and components will be used? / Where will they come from? / How much will they cost?
| Qty | Description | Price | Link | Notes |
|---|---|---|---|---|
| 1 | Power Supply | $26.95 | Link | AC to 12v DC - Low Height Profile |
| 1 | AC Power Adapter | $8.99 | Link | Rocker Switch for Power Control - Inline Fuse |
| 1 | Water Pump | $24.99 | Link | 12v - 9mm outlet - 130GPH |
| 2m / 6.6ft | 9mm Silicon Tubing | $10.49 | Link | N/A |
| 5m / 16.4ft | Grow Light Strips | $13.99 | Link | 4 Red : 1 Blue |
| 5m / 16.4ft | White Light Strips | $11.99 | Link | N/A |
| 1 | pH Sensor | $66.99 | Link | N/A |
| 1 | Electrical Isolation Board | $16.99 | Link | N/A |
| 50cm - 120p | Female to Female Jumper Cables | $13.99 | Link | N/A |
| 1.75mm - 1kg | White PETG | $23.99 | Link | N/A |
| 2lb | Aquaponics Beads | $11.95 | Link | N/A |
| 5oz Tube | WeldOn 16 | $17.90 | Link | N/A |
| 10.1oz Caulk Tube | All Purpose Clear Silicone | $5.38 | Link | N/A |
Total Cost: $254.59
What parts and systems will be made?¶
Breaking down my Assistive Aquaponics Fish Tank into systems is a pretty straightforward task due to the nature of aquaponics combining two different subsystems, aquaculture, and hydroponics. With that in mind, my tank is split into two main systems, a plant box, and water moving system, and a fish tank and structure, each interweaved with my project’s third system, the tank’s electronics. I’m trying to produces as many of the components making up these systems as possible, from the tank’s structure to the acrylic fish tank, to all microcontroller boards on the project.
What processes will be used?¶
- CAD work - For planning & Designing All Files the Following Processing Will Use
- CNC Milling - Plywood Tank Structure
- Laser Cutting - Tank Front Plate, Acrylic Tank Panels, Other Bits & Bobs
- Electronics Design & Production - Tank Main Board, pH Board, LCD Breakout, Temp/Humidity Board, Power Breakout Board
- 3D Printing - Electronics Mounting & Cable Management
What questions need to be answered?¶
How does the Aquaponics Ecosystem Work?¶
Building off of my prior research into the topic while conceptualizing my Assistive Aquaponics Fish Tank, I took a deeper dive into the workings of the Aquaponics Ecosystem. The video below offers a pretty good summary of the ecosystem, while also comparing the theoretical ecosystem to a real aquaponics setup.
When in balance, six steps create a successful aquaponics ecosystem…
…where all parts of the system rely on the others, a process known as recirculation. The aquatic life of the tank contributes poop and waste food into the ecosystem, creating ammonia, toxicity for the fish, in the water in the process. This generated ammonia is then converted into helpful Nitrites, and eventually, Nitrates by bacteria in the system through a natural process called The Nitrification Cycle, after which, the system’s plants absorb these Nitades as plant food, filtering the water in the process, and therefore the eliminating any harmful ammonia in the system’s water, returning the system to its starting place. The six major players in the system, Fish, Plants, Bacteria, Ammonia, Nitrites, and Nitrates, rotate around this six-step ecosystem repeatedly, and when kept intolerant with each other, create the thriving aquaponics ecosystem I’m looking for in creating my aquaponics fish tank. In The Effectiveness of Aquaponic Compared to Modified Conventional Aquaculture for Improved of Ammonia, Nitrite, and Nitrate, an academy journal article written by Deswati, Amelliza Deviona, Ella Intan Sari, Yulizar Yusuf, and Hilfi Pardi for the Rasayan Journal of Chemistry, elements of the aquaponic system are analyzed, and some ideal thresholds are given for a balanced system between Fish, Plants, Bacteria, Ammonia, Nitrites, and Nitrates, all with included real-life large scale aquaponics systems. I found this journal super helpful with providing application to aquaponics and also expanding my understanding of the components of the ecosystem through the journal’s experiments.
Deswati, et al. “The Effectiveness of Aquaponic Compared to Modified Conventional Aquaculture for Improved of Ammonia, Nitrite, and Nitrate.” Rasayan Journal of Chemistry, vol. 13, no. 1, Jan. 2020, p. 1. EBSCOhost, search.ebscohost.com/login.aspx?direct=true&db=edb&AN=142699175&site=eds-live.
What Grow Medium to Choose?¶
A crucial part of an aquaponics system, the growing medium is not only the place where plants are grown but also where the Nitrification Cycle of the system takes place. This cycle is optimized with more surface area, a contributing factor to the types of grow mediums used in an aquaponics tank. The video below, along with its corresponding article covers some different types of growing media, along with some background knowledge of its necessity.
In the case of my tank, I settled on using LECA expanded clay pebbles (Aquaponics Beads) for growing media. These expanded clay pebbles are filled with pores, allowing for the transfer of more water, and also an increased surface area for the Nitrification Cycle to take place.
What’s a Suitable pH threshold for my Tank & How does a pH Probe Operate to Measure It?¶
Keeping the different elements of an Aquaponics Ecosystem in check is crucial for the success of the system. I’m planning on using goldfish in my Aquaponics tank due to their natural hardness. To keep the ammonia produced by these goldfish in check, and in their ideal threshold “between 7.0 and 8.4”(Gold Fish Care Sheet) pH values, my Assistive Aquaponics Fish Tank will use a pH probe to monitor the pH and Ammonias in the water of my tank at all times. This pH probe form Atlas Scientific comes with a great operation principal description on the probes datasheet, with highlights included below.
“A pH (potential of Hydrogen) probe measures the hydrogen ion activity in a liquid. At the tip of a pH probe is a glass membrane. This glass membrane permits hydrogen ions from the liquid being measured to defuse into the outer layer of the glass, while larger ions remain in the solution. The difference in the concentration of hydrogen ions (outside the probe vs. inside the probe) creates a VERY small current. This current is proportional to the concentration of hydrogen ions in the liquid being measured.” (pH Probe Datasheet)
“A pH electrode is a passive device that detects a current generated from hydrogen ion activity. This current (which can be positive or negative) is very weak and cannot be detected with a multimeter, or an analog to digital converter. This weak electrical signal can easily be disrupted and care should be taken to only use proper connectors and cables … The current that is generated from the hydrogen ion activity is the reciprocal of that activity and can be predicted using [the equation pictured below]” (pH Probe Datasheet)
- Where R is the ideal gas constant
- T is the temperature in Kelvin
- F is the Faraday constant
How will it be evaluated?¶
My Assistive Aquaponics Fish Tank will be evaluated through the use of the ecosystem itself alongside the assistive features offered by my fish tank. The final product should offer a relatively time-efficient way to maintain fish & plants, and after the project’s completion, I’m planning on keeping track of the progress of my tank’s ecosystem in a weekly tracking journal on this website.