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The Massive and Passive Hydroponic System Project

Posted by danielfp (My Page) on
Wed, Sep 1, 10 at 12:18

Hello Everyone,

Today I want to share with you a very interesting project I have decided to start to learn more about passive hydroponic systems and their potential to replace large parts of modern rural agriculture in third world countries.

This project - which I am calling the Massive and Passive Hydroponic System Project - seeks to gather information from hydroponic growers all around the world who want to use and implement passive hydroponic systems that use absolutely no electricity and a minimal amount of water.

If you would like to learn more about the project, its objectives and how you too can participate and help us build a better world please download the pdf I have made available here :

Setting up these systems is extremely easy and you will definitely learn a lot about the building of hydroponic setups with absolutely no recirculation or electricity from your experience :o)

Thank you very much for all your interest !

Best Regards,


Follow-Up Postings:

RE: The Massive and Passive Hydroponic System Project

I'm not able to participate in something like this but I've been lurking in this forum recently because I am interested in passive hydro for some house plants. Thanks for the info on your blog.


RE: The Massive and Passive Hydroponic System Project

Hello Danny,

Thank you for your follow-up :o). It's too bad you cannot participate, however I am glad that the information in my blog has been useful,


RE: The Massive and Passive Hydroponic System Project


In case you're interested, my system is passive:


I also have some ideas for passively maintaining ppm that I haven't had a chance to try yet. Picture a tank with a constant osmotic pressure, maintained as such by the presence of a high-molecular-weight, poorly biodegradable solute (there are many options). Connected to the tank is dialysis tubing inside your grow bins. The minerals in the grow tank can pass through the tubing, but the high molecular weight solute cannot. Osmotic pressure should ensure that most of the salts remain within their respective grow bins, and that they're diluted to the same osmotic pressure as your solute tank. Thus, so long as the water level in the solute tank remains constant, so should the ppm of your grow bins. You can maintain the water level of your solute tank with a float valve -- the same type that you find in a toilet.

Again, I haven't tried it, but I can't see a reason why it wouldn't work.

Likewise, you could add nutrients passively. As your plants absorb their mineral salts, the amount of water needed to maintain a constant ppm will drop -- i.e., the water level will drop. So a second float valve, this time in the plant grow bins, could be used to add more nutrient solution.

The one thing that this wouldn't take care of is the ratios between different nutrients, which can change over time, depending on what your plants are hungry for. I've thought of several ways to take care of this automatically, but they're anything but simple or cheap, and generally involve reverse osmosis and/or ion-selective membranes and/or automated nutrient testing systems.

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