Hi farmers !
First, I would like to thank all the many contributors of the site, because you were to me a great source of information and inspiration.
I am now proud to present my set-up wich is now running rather reliably since around one month.
My “near the window” farm is composed of an aquarium pump (450 l/h flow) dipped into the nutrients solution. I connected this pump to a drop by drop tubing system (4.6 mm diameter) easily available from gardening shops, which allowed lifting up water to around 70 cm height. To be honest, my initial plan was to build an air-lift system, but in spite of many hours spent testing it in my bathroom, I never managed to get satisfactory and reliable results. Also, I felt somehow disturbed by the noise of both the pump and the bubling, which is not the case with aquarium pump.
I cut plastic bottles (and made little holes in the cap, so I could insert a tube inside) and filled them with clay pellets. These plastic containers were placed into clay pots (for aesthetic reasons) that were attached to shelf rack, so the plants can be easily moved to different places… and voilà I am currently growing tomatoes, red peppers, strawberries, melons and eggplants !!