Hi Evan
A simple constant flood growbed , keep it long and narrow if you can , up to twice your fish tank volume
Long and narrow will avoid any "Low Flow" areas in your growbed , water is one end and out the other end
You will need good light to grow healthy plants , so a really good sight like a sun room , or artificial lighting
You may be able to reflect light in a window to improve natural light
On a smaller scale a growbed above the Aquarium is often done
Maybe a window box planter would work for you
Water runs in pipes so your growbed can be some distance from your aquarium
Just floating plants on top of your fish water will be disappointing long term
Search "Aquarium Aquaponics" in images for ideas
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