Spread the gravel 1 inch deep in the floor of the aquarium.
Mix 1 part soil, 1 part vermiculite, and 3 parts sand together and spread on top of the gravel. Shape the sand and soil so it slopes up toward the back of the aquarium.
Place several cacti and succulents in the soil and provide them with water.
Place rocks on the soil for decoration.
Attach a thermometer to the aquarium so you can closely monitor the temperature inside.
Place desert-dwelling animals such as insects and arachnids in your aquarium, after you allow the ecosystem to reach a level temperature. Periodically spritz the cacti and succulents with water.