I started a 400 sf greenhouse in January to house my first aquaponic system. I decided to use a 275 gallon IBC in the ground for a tank. I have 4 half barrels for media beds with river rock. I plan to expand and have another 6 or 8 grow beds by the end of the summer. I found a really helpful youtube link that will help calculate the amount of media needed per pound of fish based on the type of media.
I have been cycling the system with gold fish for about two months. I have nitrites and nitrates present and starting to see a little growth in the grow beds. It has been a lot of work but I hope it will pay off this fall and over the winter and by next summer I would really like to have another IBC or two and have the greenhouse full of grow beds.