In this part, we will take a look at hydroponics arranged in a box, like those that hang on windows, outside.
Rectangular plastic container holds about 10 liters of solution, it can accommodate some eight single plants (in plastic cups) or we can put a few mini-pallets with greens.
The idea is that we place some (depending on the length of the container) number of transverse holders, and in them, in turn, place either cups with plants:
... or mini pods with greens:
Few important points here.
First, the transverse strips that fix the structure in the flower box:
Second, vertical cylinders with holes - you can insert sticks into them, put on top of those sticks connectors (see above) and voila! - we have a support system for our plants.
Third, either round holes for cups, or a large rectangular hole into which a 3D-printed lattice tank is lowered. This tank can be placed in a tray with water, then you put a napkin in it and place some seeds. When the seeds germinate (more precisely, when their roots will grapple with the napkin), the tank can be placed on the holder and all together - in a flower container box. There will be a nutrient solution underneath, plus the spray created by the compressor, so, the napkin will be wet:
The same principle applies to holders with round holes: we make sure plant is fixed in a cup one way or another, then the cup is placed in the holder, and together they are installed in the box.
On the last photo you can see a holder of the third type, equipped with something like a locomotive pipe. This is not really a holder meant to have plants in it, instead it combines a funnel to add liquid to the tank and a sensory well (manhole with cover). On the same picture you can see the hatch (closed with a green lid) into which we plan to lower the compressor hose:
When growing strawberries from seeds, or anything else with seeds that small, you wouldn't be able to move the tiny plant into the hole in a plastic disk. You especially can not do it, if you have a farm with hundreds or even thousand plants.
A convenient solution is to use substrate, but we decided to not use substrates, as they introduce unwanted organics and germs in the system. So let's use inorganic substrates: mineral wool (use only agricultural one, construction mineral wool is out of question as it contains additional components that can be toxic!) or sand.
Here is sand, protected with plastic napkin so it isn't washed away.
Also, I boiled this sand to kill germs.