This is designed with low power, low maintenance, and low cost in mind. Also, I have designed it to be able to house multiple generations and species of fish at once so re-stocking would not be requied for the average person's back yard. It can even house multiple bait fish and crustation species for a balanced ecosystem.
This system has a 15ft above ground pool at it's core. I have integrated a ring of stacked milk crate baskets in the center that are filled with gravel for biological surface area. The milk crates are stacked to allow skinny pan fish and smaller younger fish to enter and be in a protected safe zone in the middle and still have food brought to them by the whirl pool effect. The baskets can be planted out with things that provide cover, breeding grounds, and food for the fish.
In the middle of the ring of milk crate baskets there is an airlift that brings in waste water from the outer ring and force feeds it through the biological surface area of the gravel within the baskets. As well as bringing in food for the crayfish and what not.
There are two rings of airlift bubblers at the edge that will create a constant but slow current in a clockwise direction in the Norther hemosphere. These in their current setting will just be hung on the edge of the pool. If you wanted more flow you could create something that looks like an exhaust manifold from a car engine. One large inlet that splits to pultiple outlets. Less points to form leaks. Anyways, the current is great for trout or channel catfish. As they almost require it and are almost the most efficient growers. A trout can be harvested after 6 months.
The solids lift overflow is also harvesting from just outside the milk crate ring. May work better from inside the ring. The horizontal pipes are placed just off of the water surface to provde a way to hold the floating lettuce rafts. The green circles on those rafts are about 7 inches.
The lemon trees would best be Meyer Lemons as they produce multiple yeilds every year and the fruit can hang for up to 5 months. Of course something else could be grown.
All of the raised beds are wicking beds. They can be watered with either the rich aquaponics water or the fresh rain water from the rain storage on the North Wall. Those white boxes used for rain storage are litterally the dimensions for the 330gal IBC tanks. Just for point of reference. They are stackable. So those 12 tanks would hold about 4000 gallons of water. I would recommend slanting the whole roof to one side for complete and easy routing of harvest. You can insulate the roof easier during the Winter that way as well for heat retention.
This system will not drain the entire pool. If one of the Constant flood IBC bed's drains become clogged and water goes everywhere. The main pools water can only drop about 4" before the air lift does not work anymore. Saving the fish.