I recently came across an exciting Twitter post by Sebastian Cocioba, describing his implementation of a simple hydroponics system called Falcoponics.
Falcoponics Testing out reusing 50mL tubes as standing hydroponic systems using rockwool and a 3D printed collar. Tobacco, brassica, and mimulus to test. I left space for a tubing line for automated watering too. Fun times ahead!Sebastian S. Cocioba🪄🥦 (@ATinyGreenCell) April 13, 2023
The system is currently pretty simple and based on 50 mL Falcon tubes that are commonly used in the lab. The tubes can be easily washed after use and reused to grow plants instead of ending up in the trash. The tubes are fitted with two 3D printed collars that secure rockwool plugs for soil-free plant cultivation.
The great thing about this system is that there is a lot of potential for further development using Falcon tubes as subunits of a bigger modular system.
Materials
- Rockwool plugs (20 x 27 mm)
- 50 mL Falcon tubes
- 3D printed collars (PETG or PLA)
- Plant seeds of your choice
Getting Started
I decided to give it a shot and bought some rockwool plugs from Amazon and took some old Falcon tubes from the lab that I washed thoroughly. It is obvious, but if you plan to eat the plants you are growing, make sure that you don’t use any Falcon tubes that contained dangerous or toxic chemicals.
Printing the Collars
I got the 3D model for the collars from Sebastians printables site. I used a Prusa MK3S 3D printer to print the collars for the Falcon tubes. As material, both PLA and PETG work probably equaly well, but for my print, I used PETG.
Since the collars are pretty simple and don’t need any support, I just used standard settings for this print.
- Material: PETG
- Nozzle size: 0.4 mm
- Layer height: 0.15 mm
- Bed temperature: 70°C
- Nozzle temperature: 230°C
Assembly
The collar fits nicely into the Falcon tube and even has some space at the sides that can be used for tubing in the future.
As recommended by Sebastian I used gloves for the next steps.
I carefully made the rockwool wet by letting cold water run through it and placed two Arugula (Eruca vesicaria) seeds into the little pocket on top. I chose Arugula seeds because these plants usually grow pretty well, and I still had some seeds that I harvested from the last plants I grew. Also, it’s tasty!
Next, I put the rockwool in between the collars and into the Falcon tube. I filled the tube with enough water to just touch the bottom of the rockwool.
Because I do not have a grow light (yet!) I found a sunny location for the tubes.
On day 4 I replaced the water with a commercial hydroponics nutrient solution.
Maintenance
Especially in the beginning it is important to keep the rockwool wet since the plants do not yet have long enough roots to reach any water that is located below.
After the plants germinated and developed small roots, I switched the water to a commercial hydroponics nutrient solution. I plan on testing my own growth solutions in the future.