Easy DIY hydroponics kit

I'm designing a DIY water farming system. The ideas come from the zengrow.com machines, which have a very simple working principle. It doesn't suit all edible plants as is, but is great for the kinds that you can buy pregrown in little plastic pots.

Btw. I'm in no way affiliated with zengrow.com, they just happen to sell useful stuff ;). Another good source is http://gb.eurohydro.com/waterfarm.html and their distributors.

Update:
I've now printed the tube connector. It feels good, we'll see how much it leaks :). A bit of leaking doesn't hurt, as long as most of the water goes where it should be. Another concerns is how noisy it is, since my hacked up system was horrible in that regard. Now I'm printing the plant holder...

It works! See the new pics. I've compactified the plant holder parts, but it's still too big for these containers that I have, and not strictly necessary, as can be seen from the pics. But especially for bigger non round containers, it should be useful for g