I recently attempted to grow fresh food in the basement, especially during the long and cold winter months. The method I settled on is the Nutrient-Film-Technique (NFT). The support rack was mainly built from square beams, and plastic ventilation ducts were used to create channels for the plants. These channels were sealed with 3D printed endcaps and a bit of silicone.

For the reservoir, I used a 40-liter storage container housing both the pump and a small airstone that provides extra aeration to the water.

I used lights are 6400K LED tube lights, fitted into a simple socket and suspended using a ratchet system that I designed. I am really happy with how it turned out.

I added fans to ensure there is enough circulation, and they are on a timer that turns on for a few minutes every hour.

I used NovaMax liquid fertilizer, and it works brilliantly. At this stage, I have some nice strawberries ripening, and we also had more lettuce than a small village could consume. Surprisingly, this system is also excellent for making cuttings, and I need to stop placing every pruned stick into it, as roots form very easily.

Overall, everything it works well, but there are several things that could be improved (some of these I can or will do on the current setup).

The spillway system was improved. It was made to drain any water in the case that any of the downstream pipes block. Initially it was linked into the main drainage pipe but I decided to connect it to its own dainage pipe to ensure it function even if the main pipe becomes clogged.

The slopes are way too shallow. The pipes are too small for the water to flow throught it fast enough to create a film. This combined with the channels not being completely flat makes the water pool in some places. Although the whole system it works reasonably well I think the pooling requires the additioal aearation which might not be needed in a proper setup. The next NFT system I buid will have much steeper slopes.

I want to double the number of lights. I think this works okay for lettuce, but more light will be better. I have a small Kratky system with much more light, and the plants do seem to grow a bit better.

Take care not to introduce pests! My lettuce seedlings got a few aphids, and once they took hold, it was really difficult to deal with them. I know the source, and it was a simple mistake (i.e., keep your seedling trays far from the plants you bring inside for winter). The whole system was cleaned, all plants were removed, and fed to the wild hares. The new lettuce crop is currently germinating.

Next, I will plant more leafy greens (lettuce, basil, spinach, etc.). I know that fruiting plants and leafy plants do not necessarily work well in the same system, and I will probably optimize for one or two crops that work well – but this also means that there might be more hydroponic systems in the basement soon (spoiler: there is already one more).

Stay tuned for the next project.

R

Note: STL files for all parts (those that were printed or cut) are available on request.