If your toes are already wet in the wide-world of aquaponics, you probably know there are as many ways to set up your system as there are fish in the sea. Part of the fun is helping to engineer and develop new ways to improve systems that maintain a higher water-quality and to increase plant production in a sustainable manner that is balanced with needs of the fish. Also important to consider is maintenance time/avoiding disasters. For more on what NOT to do, see my first post.
I came across this interesting site (http://bioponica.net) while researching different system designs. They propose a method of soaking different proportions of grasses and weeds ("dynamic accumulators") that allow for cheap and bio available "organic" nutrients. I use quotation marks because it is an "organic" practice; but in fact the plant-available form of a nutrient is referred to as "inorganic" after it has been digested by the organic matter (it's confusing and ridiculous, I know). Anyway, Bioponica is using a hybrid method of using both fish and "compost" to derive organic plant fertilizer all within hydroponic system. Most fish will also feast on the decaying plant matter as it gets mushy and seeps from the side of the mesh bag. Smaller fish also enjoy snacking on the algae that will probably grow on the sides. Duckweed may also be grown in this system from the excess nutrients, then fed to the fish.
Bioponica has been in-action for years, but I haven't seen any others running with the idea yet. There may be some kinks to work out. I suspect nutrient density and undesirable anaerobic growth to be two of those kinks; however I believe that it would only take minor adjustments to work this out, and it could be a great way to supplement nutrition! Certain weeds are known to accumulate certain nutrients in rich amounts. Fish waste is great for nitrogen, but not so much for some other nutrients-- iron being a common one. If you do a search in Google on "nutrient accumulator" or
"dynamic accumulators" you should be able to find a few lists and charts. I find mine in a highly-recommended permaculture book called 'Gaia's Garden' by Toby Hemenway. Here is a link to a post at 'Permies': https://permies.com/t/19885/list-dynamic-accumulators-minerals-accumulate
If in doubt, the fallen leaves of a large deciduous tree usually are a good store of a wide range of nutrients. A single nutrient testing has also suggested that leaf mold is even superior to adding (Azomite) rock dust in the amount of nutrients it returned to the soil. The deep roots of a large tree will effectively "mine" nutrients from the mineral-rick soil sub-layers, and convert them into bio-available fertilizer in their leaves to fall and decompose on the soil surface. Ah, the wonders of nature!
THE MEAT & POTATOES:
Bioponics is essentially a 4 part process: anaerobic decomposition, filtration, aeration, and aerobic decomposition; but depending on your system one or more of these parts may be omitted and/or already achieved in your system (such as aeration).
1- Anaerobic decomposition happens when you submerge tightly packed weeds/grasses into either a "bio-digester"/aquaponics system/body of water and let it sit for a while, without any aeration. The anaerobic process with automatically start from the native bio
2- The filtration process is basically a clarification that will remove the bulk of the anaerobic microbes and leave behind their byproducts (the nutrients) in the water. It is the step where you remove solids that can clog up the works in your system.
3- Aeration is where you begin to create a favorable environment for aerobic microbes to further digest the nutrients. It simply consists of agitating the water in order to aerate, but also I (somewhat) believe that there is a structural component as well partially because of a documentary called 'The Secrets of Water' in which Viktor Shauberger explains that water flowing in a winding, rocky river often creates vortices, or whirlpools, which oxygenate and re-structure it. It is an interesting idea, which apparently have some merit (some companies at the end of the documentary tout improvements in their industrial processes such as bread that rises better with less yeast, less calcification in pipes, etc.,)
4-Aerobic composition is where you finally acclimate the water to an aquaponics system, which is ideally highly aerated and rich with a healthy population of aerobic and anaerobic bacteria. It is also the final stage in the decomposition process where the organic nutrients in the grasses are turned into a bio-available form for plant uptake (which ironically are called inorganic nutrients).
I had a good feeling about this technique upon discovery but I admit was skeptical. How could such an abundant and cheap resource be so valuable if no one else is pursuing it? Apparently the project is still alive and growing, as I see the last post was June of this year. Good to see, and I will be following the progress for when I move to a place which has a suitable growing spot again! Here's the post: http://bioponica.net/biofarm-excellent-growth-at-one-month/
'The Secrets of Water' (about how movement of water affects it's quality) (
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