I was thinking of making a rice paddy aquarium that's designed to dry out like real world rice paddies. I'd like to use loamy clay soil as the substrate. And I may possibly add crushed eggshells or chicken bones depending on how acidic the end result is and depending on acidic drift. Clean egg shells help if it's too acidic, and dirty eggs or chicken bones may make the tank more acidic due to the organic detritus being consumed.(I'm not entirely sure on the dirty egg shell hypothesis tho.) I would form the substrate into a 30 degree sloping hill. The top of the hill will be in the back of the tank. The substrate at the lowest point(the front viewing area of the tank), would be 3 inches deep. And the substrate at the point in the back would be 7 inches deep. The highest the water will get is 13 inches.(this is starting from the bottom of the tank itself.) The variety of rice I'd like to use would the deepwater Chao Phraya river basin rice. Which grows between 3 feet - 3 feet and 8 inches tall. Hopefully 4 or more of this 3-foot plant will be under the water when it's at the highest. pic unrelated (1/2)