Good article, with three different systems which you can build. The smallest for about $10-20.
http://besurvival.com/tips-and-tricks/diy-beginner-aquaponics-projectsThe article covers most of the "basics" of how these systems operate. You will need to gain experience on "fine-tuning" such systems.
DO NOTE: with rare exceptions, these systems require electric power, 24/7, to operate. SO they will go down if you lose power... This is not a problem for SHORT time periods, say up to one or two hours, but the fish need aeration and the plants need flowing, nutrient loaded water. A generator backup or solar charged battery system is a wise addition to the system.
[edit] There are several videos in the article which you can watch and/or capture for your documentation.