One of my prototypes (nursery and pumkins)
When building your own hydroponic prototypes, one should keep in mind that what you actually need is rather simple and stupid. You need a reservoir, something to hold your plants and some media, as well as a pump, drippers or any kind of water (or air) distribution. It should be watertight and functional, easy to maintain and clean. After many sophisticated designs and prototypes, I came to the conclusion that for a long time I have overdone it with tubes and options that weren't actually necessary.
This prototype (initially planed as nursery station) is using a kinda drip and recycle X "NFT" concept. Media is coarse sand and rice hull mix, but other media (as clay pebbles) can be used. The building material is worth the equivalent of some 15 USD here in Thailand. If you have got a 5 watt pump and 140 L reservoir already, you can have it for that money in the US or EU as well. Both supports (left and right side) could also be from metal or wood, depending of availability of materials and skills. Von 3D- 24/06/09 .
I know, the place is kinda dirty, but the picture was taken before I cleaned up those salts that actually provide from an earlier type that wasn't 100% watertight ;-)
The seeds of the pumpkins (chirimen type) were planted at the edge of the support. The roots were then slowly growing down "the ramp" and finally reached the reservori, where they now need to get trimmed from time to time. Nutrition uptake and growth rate with pumpkins is excellent with this setup.