Hi,
Just wanted to share a self developped hydroponics system with all of you. Those who like to try it may allways post their experiences here and eventually which plants they growed in it. Following text is copied from my website with the instructions and a drawing of the system.
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Tests have prooved that the eb and flow- principle, where the roots of plants are sequently flooded with water and exposed to fresh air, yields more harvests and a faster growth.
Installing your own irrigation system which works with the eb & flow principle, can be expensive and complikated while it's sensitive for failures and a source of electricity is needed for running the pump system.
As a solution, I developped an alternative method which works with gravity, is trustable, easy to build and only requires a plastic bottle, two tubes, an extra tube with dripper and a glass or bowl with a gutter on it.
The watersupply must be mounted higher than the pot or tray with your plants. This can be realised by hanging up a tin of water with a piece of rope. The mechanism can be started by putting the upper side of each tube under water and suck on the downside of them until the water starts flowing down.
An experimental version of this irrigationsystem was installed in my small greenhouse during my trip to Switserland in july 2007 to keep my young plants alive when I was absent. When I came back one week later, the system was still running properly which prooves its ability to worrk independent for a longer time.
As you can see in this picture, the dripper will have filled the plastic bottle to the point where you have sticked the plastic tube trough it. At this point, water will start flowing trough the tube while underpressure will keep it running until the whole bottle is empty again. Meanwhile, the waterlevel in your plant tray will rise, and water will start flowing via the second tube to the bowl. Exces water will flow out via the gutter which causes the waterlevel in the plant tray to decrease slowly, and the next cycle will start. The process will repeat itself until the watersupply is empty.
Notes:
1. The bigger your watersupply is, the longer this system will work independently.
2. By pushing the tube deeper in the plastic bottle, the ammount of water flowing trough the plant tray each cycle will be higher but the cycles will take more time so the average ammount of water used per hour won't change. However, this is a way to adjust the system to optimalize your results.
3. By letting the dripper drip faster, the ammount of water flowing trough the plant tray each cycle won't change, but the cycles will take less time so the average amount of water used per hour will increase. This is a way to adjust the system when plants start to use more water (specially when the weather is hot or the plants get bigger) Mostly the drippers for irrigation are adjustable, but if they aren't, you can put a piece of rubber in the tube and punch one or more holes in it with a small needle.
4. The minimum waterlevel between two cycles can be adjusted by placing the bowl with gutter higher or lower.
5. Pay extra attention for plants with a high water demand. When the waterlevel gets below the end of the tube which goes to the bowl, the tube will soak up air, causing the system to fail. During the next cycle, water won't escape anymore and your plants will get drowned with rotting roots if the failure is not discovered in time. You can avoid this by tilting the tray at one side so the water will flow together and the tube will stay underwater easier. Keep in mind that the other side might stay too long above waterlevel, causing the plants to dry out there. In some plant stores you can find plant pots or trays placed on feets. When those feets are hollow and in direct contakt with the rest of the pot, you can put the end of your tube in such a feet and it will allways stay underwater, even if the pot gets dry between two cycles.
6. Specially in summertime or when you use much lighting, algae might form in the tubes and they will get clogged. You can prevent this by using tubes from black plastic or rubber. The plastic bottle should also be packed with light absorbing materials in such conditions.
7. By cutting small sleeves in the outer end of the tube you can prevent it from getting clogged with dust or sand when it touches the bottom of the tray.
8. The dripper gets also clogged very easily. Usually there's a small filter built in it to prevent this, but if it isn't (or you make a dripping system yourself) you can replace it by putting a piece of pond filter, a piece of scraping sponge or some other porous material in the inflow side of the tube.
