Aquaponics - Rainwater tanks

I managed to get some rainwater tank freebies from friends doing some back garden renovations.
The plan for my new aquaponics system is to turn one of them into a pair of grow beds, and the other into a sump tank.

The rainwater tanks measure approximately 1100mm by 1750mm by 600mm. This should allow me to split  one along the seam as garden beds and use the other as a sump tank. More on sump tanks later.

One tank split into two grow beds allows a perfect size to work with. Garden beds should be around 300 mm deep as the bacteria and plants both enjoy this depth. I will have two beds measuring 300mm deep and 1100mm x 1750mm in area. This is great because the longest my arms will need to be is just over half a meter in order to reach all of the grow beds with ease. I have arm to spare.

This is the site I'm working with. It is almost flat and is edged by a slope which will work perfectly.

Watch this space!