Hydroponics

Every blog and article I have read about hydroponics is either too high-tech or too plastics friendly, so I am asking if anyone has built a hydro system solely out of natural or at leas biodegradable materials.

Background: My partner's father's pond's altitude is below the neighbor's horse field.  The neighbor won't move the horses, and the pond can no longer support fish because of the chemical imbalances from too much manure running downhill when it rains.  My pet solution, which we haven't tried out yet, would be to float hydroponic rafts on the pond, growing greens of every variety, which should help balance the nitrogen problem and give us chard, spinach, any-leaf and every-leaf I can imagine to sell to market.

I really don't want to use styrofoam (although I have thought about sewing sheaths for foam so at least when it deteriorates it's in a bag, not the water directly) and I don't know much about how PVC or other piping would do as support floats.  Wood nominally floats, but only for about a season....Help?

Renee, I like this idea a lot!

Some thoughts that I immediately had are:

Some species of wood are surprisingly durable when kept wet. If you could weigh down the rafts so that the wooden floats are *just* under the surface, you may be surprised how long they last! I recommend elm and alder as two candidates to try for this.

Other species might actually grow into living rafts. Some willows will drop branches into rivers as a way of propagating themselves; these branches float, grow roots and leaves, then float downstream and lodge into banks. If you don't mind pruning the rafts, you could try green willow logs, tethered in the center of the pond.

You might also wish to try planting remedial species along the uphill bank. These might intercept some of the manure and remove the nitrogen before it beings to eutrophy the water. Willows, poplars, reeds and some of the species I mention here.

While I don't have first-hand experience, here are some plastic-free choices:

Using Grow Poles for Hydroponic Systems: An Eco-Friendly Alternative to Plastic

Grow poles are vertical structures used to support and train vertically grown plants. They are typically made from natural coir along with latex supported from wood, pvc or a combination of both and can be installed in a variety of ways, including in rows or clusters. The purpose of grow poles is to provide plants with support as they grow, allowing them to reach their full potential.

https://growbycoco.com/using-grow-poles-for-hydroponic-systems-an-eco-friendly-alternative-to-plastic/

Plastic-free grow boxes:



I hope some folks that have used these will let us know how these worked out.

Luke Mitchell wrote:

You might also wish to try planting remedial species along the uphill bank. These might intercept some of the manure and remove the nitrogen before it beings to eutrophy the water. Willows, poplars, reeds and some of the species I mention here.

We definitely have been working to determine what to plant on the hill.  Some of the issue is water retention as well, and so we did a survey and cut some lines, which definitely helped.  There hasn't been a huge algae bloom since then, but still small ones, and the fish are few and far between but there's a billion bullfrogs, so I know the water's livable now.  I am thinking about high-nitrogen fruiting trees, but they're not really a thing.

I know there aren't any large willow nearby, but I shall have to check what trees are growing along the dam.  They all need taken down anyway, and I like the idea of repurposing them into the necessary logs for growing floats.  Maybe we could even drill holes directly into the logs for the plants to live in...my backyard maple tree has Spanish Needle growing in it's crook, so anything's possible

Sidenote, to whomever edited my title, I am sorry you don't like wordplay.  It was intention and not a misspelling.

I am doing Krtaky hydroponics in half gallon fruit jars. Microdwarf tomatoes, green onions, basil so far. I use artificial light but a sunny window would work.

You could do floating islands or gardens in the pond or pump or hand water into gutters, pipes or buckets that your plants are growing in on land with the water going back to the pond.
You should be able to modify any of the three ideas below to work.  My plan when I get time is bottles(plastic) in coffee bags(burlap) with soil on top to grow on.
Not my pond so time is the enemy - travel back and forth.

https://www.bbc.com/future/article/20200910-the-remarkable-floating-gardens-of-bangladesh
https://www.floatingislandinternational.com/
https://offgridworld.com/diy-rain-gutter-aquaponic-system/

Large foam pads, pool noodles, PVC pipe with bottles inside, and sealed bamboo are some other floating options.  
I realize most are not natural but if you have them or get them used maybe count the re-use for good?
 
Have you thought of a filter strip between the manure source and the pond?

Good luck.

Sorry that I repeated a lot of what Luke had already posted.

another example
https://permies.com/t/58283/Floating-garden-sustainable

You can use vetiver on ground and on the pond to lower the runoff, in one to two years the roots will give you a 7m deep barrier if you put the plants on the ground, on the meantime you can float a few rafts with vetiver to quickly decrease the amount of nitrates and bacteria from the water. Vetiver grows to a height of ~2m so it will also be a wind barrier. You can find your nearest supplier in the vetiver network website.

You can make the floating rafts by sealing PVC pipes and chicken wire should be good enough to allow the vetiver to root and grow without losing flotability or having to secure grow cups

Vetiver is know to lower runoff with high efficiency ~90% and it can grow very harsh conditions and it survive frost underground if that's an issue.

It's been a while!

Here is my Test Subject #1...last year's sunflower stalks (nice and pithy like corn) with jute twine and toilet paper rolls. I am considering replacing a couple TP rolls with hardware cloth and maybe stuffing one with cheesecloth to see what sort of things the plants like best.

The pond is still icy at the edges, and midMO last frost date is early April, but I am getting really excited to launch this thing and see what happens.

Hi Renee, interesting question and your raft is looking quite good.
I think the TP rolls might desintegrate, perhaps find a more durable solution - bamboo stems (hollow) of roughly the same proportions? Also, cork floats so you might be able to use that .

Good luck, keep us posted!