Lungfish hydroponics aims to produce a modular ponics system where each module can be independent and easily switchable. It uses an external air pump to simplify the whole system. Blocked filters will be a thing of the past because there will be no filters! It is called "lungfish" because the underwater ebb and flow air container can act as a "Lung" to transfer oxygen to the nutrient solution.
Step 1: Using Easily Available Materials.
A key to widespread use of DIY hydroponics is reusing various easily available products in the system. Another key is to keep the technology as simple and as "low" as possible. A 3rd key is modularity. Parts of the system can be modular so that they can be removed or adapted or replaced by a superior module as the system matures.
Step 2: Geyser Control Module, the Only Technically Difficult Part in the Whole Project!
This is the part I need to simplify. Or replace! Because it is a modular system, a replacement that works quite differently could also perform this switching operation. In th current system it is made from an energy drink bottle and a rubber bung with 2 holes drilled in it. The tube goes into the bung to let the air out as it cycles.
Step 3: Perlite Grow Media
The perlite is put on a sink cup stand inside remay or frost cloth and the water ebbs and flows up and down through the perlite. I measure the ebb and flow distance with a simple manometer. The system does and ebb and flow cycle in just over 2 minutes on about 2 litres per minute of air from the little aquarium air pump.
Step 4: Air Pump
I used a 2 outlet aquarium bubble pump. This one is capable of 3 psi (enough to push air about 7 ft deep in water and about 2 litres per minute of air.
Step 5: Preliminary Conclusion
Step 6: "Timer and Bleed" Alternative to the Geyser Switch to Control Ebb and Flow on and Off
Another system that would probably work to control ebb and flow is "timer and bleed". In timer and bleed, your pump is on a timer and it runs for about 15 minutes, and pumps air into the basins, raising the water level. The system has a little adjustable "bleed" that you can make with an aquarium air valve. An advantage of timer and bleed is that the roots would be damp but not water logged most of the time.
Step 7: "Flip Flop" Alternative for Switching.
I made a "flip flop" to spread irrigation water from a drip feed across more area in a planter. I think this type of thing could work underwater too. So when your air gets fairly full in the basin, something flips either in it or outside it and everything empties. (Outside it is preferred to maintain the modularity of the system).