I would dig my fish pond in the ground, and place grow beds around pond so they waterfall back into pond. Waterfall=DO. Maybe 2/3 buried and 1/3 above ground.And inground pound has insulation for hot and cold,( stops temp swinging around as much), also go deeper than 30 inches. The earth deep down has real constant temperatures. Block sun from pond to minimize algie. It can also make for a real cool kick back spot with waterfalls and fish and plants. I use clay/adobe for my aquaponics, it's cheap(free), but it wreaks havoc on water PH. I live in the Mojave desert so clay is abundant, you can't get away from it. It's in the air, here. But my plants are blowing up. Fish are happy. I have spinache, tomatoes artichokes and strawberries all growing, all producing with a water PH of 8.4. Use the cob go deep, build grow beds around edge of pond power with solar leave space for kicking back in your new microclimate.
