PEX: Aquaponics

Preface:

Initially, I'm most interested in a list of aquaponics skills/knowledge.

Segmenting what belongs to what belt will emerge naturally and probably fits better after the initial skills list settles down.

I'm biased toward demonstrated skills but suggested requirements at early levels demonstrate prerequisite knowledge to starting into those skills.

Starting Requirements

These first level requirements are minimums to get someone to the point they can build, stock, plant, operate, and maintain an aquaponics system. Later requirements expand from there, without specifying belt level boundaries.

1. Briefly explain differences between nutrient film, deep water culture, and media bed systems.

Draw a rough schematic of each system type, showing key components.

Explain what function is fulfilled by each component.

Explain the the pros/cons of each of the three system types. Are there plant or fish types you'd prefer in one system vs. another.

Explain which type of system would you start with in your location and situation. Why?

2. Identify a specific aquaponics system design appropriate to your environment.

Explain the design. Why did you choose NFT or DWC or media bed? What type of fish and plants is your design intended for. When fully operational, what is the system's capacity in gallons, quantity of fish, quantity of plants?

Explain key components of your system. Explain flow rates, flood and drain mechanisms and frequency, oxygenation, etc. Explain any mechanisms for temperature control or lighting.

List any outside inputs your system will require once operational. Discuss how each of those inputs could be reduced or eliminated and the cost/benefit of each such change.

List any residuals or waste your system will output. Discuss how each of those outputs could be reduced or harnessed as an asset and the cost/benefit of each such change.

3. Identify a fish species appropriate for the above aquaponics system at your location. Explain why they are appropriate. Explain any regulatory restrictions on the fish species you've chosen. Provide source and pricing information for those species, including everything you need to place an order and receive shipment.

4. Specify plants appropriate for the above system. Explain why you chose them. Locate sources.

5. Explain how your system, once constructed, will be started up (cycled). What test kits, equipment, or supplies will you need? Where will you obtain them? What procedures will you follow, including when you will add plants and fish?

6. Build the system, start it up, and bring it up to it's full productive capacity. Operate the system through at least two plant harvest cycles and at least one full fish harvest cycle. Briefly share your key learnings through this process, with emphasis on what you'd repeat and what you'd do differently next time.

7. Personally harvest, prepare, and eat fish you've raised in an aquaponic system.

Additional requirements, possibly for higher levels

A. Design an aquaponics system appropriate to your environment. This differs from requirement two as you're the designer now, not merely copying an existing design.

Provide sufficient detail that your system could be built by a proficient DIYer who's aware of aquaponics but not an expert.

Explain the system you designed, covering at least the same material as requirement 2 above.

How does your design differ from or improve on the system you used for requirement 2? How does it differ from or improve on commonly available designs such as barrelponics or IBC systems?

Build, startup, and operate the system you designed through at least one full fish harvest cycle. Briefly share your key learnings through this process, with emphasis on what you'd repeat and what you'd do differently next time.

B. Build, startup, and operate at least one NFT system, one DWC system, and one media bed system through one full fish harvest cycle. Systems built for requirement 6 and requirement A may count toward this requirement.

C. Raise another fish species through one full fish harvest cycle. Briefly share your key learnings through this process.

D. Prepare a meal for four people, primarily from fish and plants you've raised in an aquaponic system.

E. Prepare a meal for guests, primarily from fish and plants you raised in an aquaponic system. Have the guests present as you harvest fish and plants and prepare the meal. Explain to them how the system works.

F. Operate an indoor aquaponic system using grow lights through one full fish harvest cycle. Explain light requirements for your plants including type of lighting, distance from plants, number of hours per day, and energy requirements.

G. Explain benefits of vermiponics - using worms in the media bed. Discuss additional functions stacked through vermiponics.

H. Use your system to produce your own fish food. Operate an aquaponic system through a full fish harvest cycle using no imported feed.

I. Breed your own fish.
(Caution to the uninitiated. Breeding is seriously non-trivial, except perhaps for Tilapia, which probably won't work in Paul's climate without a RMH for the fish.)

J. Expand your system to include other sea life besides the primary fish - shrimp, prawns, shelfish, whatever strikes your fancy. Explain how these additional elements support each other and fit into the system's cycles. Publish your results in sufficient detail to enable the DIY aquaponics community's to replicate or build on your experience.

And a few questions I'm pondering

None of the above requirements specify harvest quantities - other than the implications of #6 in bringing a system up to full productive capacity. Shall we add minimum harvest quantities of fish and or plants as Paul did in PEP1 - Gardening?

I'm contemplating a requirement to teach five children (under eighteen) about aquaponics, help them build systems, and mentor them through a full fish harvest cycle. This has a few legal complications as you probably need parents permission to have their kids building things and filleting fish... but it fits nicely with infecting the world with permaculture ideas. Enthusiastic kids are magic for spreading things.

Should the cooking requirements (7, D, E) be more robust? This isn't principally about cooking, but in completing requirement 6 you'll end with a lot more to eat than those few meals will consume.

Help make this better

It's a first pass from a non-expert, derrived from the path I constructed for myself and my family while studying aquaponics a few months this year.

Jump in and make it better!

How about something on water quality parameters, pest control strategies and plant nutrient deficiencies? Also maybe something more on home-produced fish food, like design and publish so other people can use it a complete home-produced fish food for 3 different fish species. And maybe the part about teaching kids could include setting up demonstration sites in schools. Aquaponics is such a good way of teaching kids (and grownups) everything from ecology to fluid dynamics. Maybe also could add something for the higher levels about setting up a system to feed people who are food insecure, like maybe in conjunction with a senior center, or a food bank, or something like that. I'm sure every community has a lot of need/opportunity.

Deb, I love your suggestion about demonstration sites in schools. Great idea! I also like the suggestions about publishing work on fish food and contributing to community food security.

I wrestled with things like pest control and nutrient deficiencies. Part of me says that's general gardening so let's leave it to that area and focus here on what's unique to aquaponics. On the other hand, perhaps some minimum amount belongs. I'm completely flexible on this one.

Water quality is different - it's unique to aquaponics. Perhaps we should have guidelines on maximum allowed deviation on water tests from target levels. I didn't really consider it as it's implicitly essential to successfully run a system through a full fish harvest cycle. However, your calling it out reminds me that I never even said what successful or a full cycle means. It certainly doesn't mean killing all the fish. Perhaps we should have guidelines on maximum acceptable fish loss?

Deb or anyone else, feel free to answer my conceptual ramblings with specific additional requirements worded as you think appropriate.

Fish can have pest problems and nutrient deficiencies too, not just the plants. And they are their own special set of challenges.

Definitely can be some challenges with breeding, and with legalities. The specific crayfish that I find most appealing as an aquaponic resident cheats on the first, resulting in it getting seriously hammered on the second. It is an hermaphroditic self fertilizing crayfish. Sort of aquatic tribbles...

A near perfect aquaponics candidate, but for those little legal issues. 😔y

Marmorkrebs, "self-cloning marbled crayfish". Couldn't remember the name, had to go dig it up again ...