Blog #3

Team: Aquaponics/Biogas

Project Updates

Recap: For one portion of our project we are designing an automated system that will transfer the fish waste from the pond, directly to the biogas unit.

After analyzing the current system in place at Middlebrook Gardens we initially thought that a weight sensor would be the best way to determine when the fish waste was at a level high enough to dump. However, upon testing the weight of both water and fish waste mixed with water, we found that there was roughly a 1% difference in weight. We had assumed that there would be a larger difference in density. We are now contemplating whether an optical sensor may work better.

Field Trip!

We had a great field trip to Ouroboros Farms this past Friday (10/5) where we learned a great deal of information from the employees at the farm as well as the owner Mr. Armstrong. It was amazing to see how “happy” the plants looked! The plants that are currently growing in the aquaponic system at Middlebrook Garden are not doing as well so it was nice to see a benchmark for what healthy plants should look like.

Pictures of the “happy” plants at Ouroboros Farms (Top: Swiss chard, Bottom: collard greens)

We were taught all about the aquaponic system, from the different types of fish, to how the seeding process for their plants’ work. It was also interesting to discover that there were also small worms and shrimp in the system that aid in process of breaking down the fish waste into more useful compounds for the plants.

The second stage of the seeding process

During our tour, we learned about the three different types of growing methods that can be used for aquaponics, media beds, NFT, and deep culture. Media beds use rocks or perlite where the plants will grow from. NFT, nutrient film technique is where the plants are grown in long narrow channels, sometimes in PVC piping, where a continuous flow of water is pumped over the roots. Deep culture (as shown in the picture to the right)

is where the plants are grown on polystyrene rafts that float on top of the water, this utilizes the space most effectively out of all the methods because so many plants can be grown close together. Mr. Armstrong also informed us of nine essential values that should be measured in an aquaponic system, these include the following: nitrogen, potassium, phosphorus, calcium, iron, magnesium, dissolved oxygen, pH, and temperature.

Project updates

We have begun by collecting everyone’s contact information, setting our availability, setting up weekly meetings, and brainstorming ideas on how to approach our project. We have met our community partner Alrie Middlebrook, who oversees the Middlebrook garden. Middlebrook garden is located in San Jose, and its primary purpose is educational feedback for kids. Middlebrook garden is where my team and I are planning to work on the project. There’s an aquaponics system, a biogas unit, and a greywater collection system. Our goal is to develop a closed-looped system that will connect these three separate units.  Grey water will be used for supplementing the fish pond, plants will grow from the nitrogenated fish excrement while also filtering the water, fish will be fed mealworms or algae, solid waste from fish will be extracted and delivered to the biogas unit, the biogas unit will produce methane which will supplement the required system energy. Our first milestone is to connect two units: the aquaponics system and biogas unit. Our second milestone will be to incorporate the greywater collection system. One of the setbacks that we are currently facing is choosing the sensors. We thought on some possible sensors that might be needed such as weight sensors, PH sensors, and mass flow rate sensors. Another setback is figuring how we are going to extract only solid waste from the storage tank and deliver it to the biogas unit.  

Articles that you found interesting that can relate to your project 

An article called “Grow Your Own Fish Feed” found from plantchicago.org, pointed toward improvements to be made to the current aquaponics system. This article also gave some ideas on how we could increase our efficiency maximizing food output. Eric Weber, the author of the article, talks about how he wants to replace the current food for fish with a more sustainable source like mealworms. Mealworms are a resilient bug that can sustain life on just about anything including coffee chaff, spent grain, spoiled plants from the farm; these are protein-rich animals and provide the essential nutrients for fish (Weber, 2018). These mealworms could be potentially supplemented with duckweed, which can also be used to feed the fish. The overall goal of this project is to create a more autonomous looped system and create more waste to be utilized; in our case, the biogas unit.

Trips to your Project Site

Our team went to visit the Project site called “Middlebrook Garden” and is located in San Jose. We met our community partner and some of the people that work there. Our community partner showed us the three units we’re working on with (aquaponics, biogas unit, and greywater collector) and shared some of the goals she would like to work on with us. Our team took some pictures of the current Aquaponics system and the garden.

Hector Garcia

Team Member Spotlight!

Hector Garcia

B.S. Mechanical Engineering, (SP 2019)

Project Manag

er, Project Archivist.

I was born and raised in Mexicali, Mexico. My hobbies are socializing with my school club SOLES, working out, playing basketball, boxing, playing video games, and watching horror movies. My favorite movie is Toy Story. My favorite subject is Thermodynamics and Heat Transfer. I joined EPICS because I wanted to create something that would help my community. My future goals are to become a certified engineer and open a restaurant with my brother.

Aaron DeMers

B.S. Mechanical Engineering (SP 2019)

Aaron DeMers

Lead Designer, Editor

As a Northern California native, I enjoy the outdoors mostly by looking at pictures of it.  Currently, my interests are the impending A.I. takeover and how humans can be useful to our algorithmic overlords. EPICS is a great opportunity to work with a community centered team while learning how to navigate a professional environment.  Moving forward, I would like to explore gene manipulation in humans so we can live forever.

Chris Fernainy

B.S. Mechanical Engineering (SP 2019)

Project Financial Officer, Assistant Designer

I have been a Californian since birth thus adopted the stereotypical values one normally associates with a resident of California. I love to surf and spend time outside when the time permits. I am a competitive swimmer turned novice triathlete. My favorite movie is Frozen, I guess I must be a little kid at heart. I joined EPICS because helping out the local community while learning about engineering at a hands-on level seemed like an excellent s

enior project. My future plans are to enter the field of renewable energy, most likely continuing my education to study wave and tidal power.

Chris Fernainy

Lok Hin Yu

B.S. Computer Engineering. (SP 2020)

Tech Specialist/Webmaster

I grew up in Hong Kong and moved to the states during 7th grade. I love to exercise and doing outdoor activities such as hiking and camping. My favorite movie is v for vendetta which teaches me how to stand for an idea. EPICS gives me a way to serve my community to make it a better place and offers a sense of working with people with a real project which have an actual impact to human life. My future plan is to be certificated as a LEED Green Associate.