Hi Jenny,
Hydroponics is the same except for the nutrients.
With aquaponics you just need to feed the fish and top up the water levels.

With normal hydroponics you have to mix the nutrients and change the solution every few weeks, so you have to pour the water somewhere.

I prefer the feeding the fish and topping up the water option plus its organic

The fish to water ratio is about 1.6" of fish to 4.5 ltrs of water.
I will probably have a lot more in the actual greenhouse system.
All the fish are quite large from 200mm to 350mm.

The experiment uses 20 ltrs in a tub with 5 chilli plants to test how much nitrate is used in a week, so far the it`s hardly measurable.

I took some new pics yesterday to keep the album updated:
http://usera.imagecave.com/Geo/Greenhouse/

The plants are deep green (except where the camera flash is) and have begun to show flower stems (like pods?)

I`ve not grown chillies before so i`ve little idea what to expect

Geo