Build an Aquarium Terrarium You\u0027ll need these materials: A small to medium size aquarium Charcoal (finely ground) Small pebbles Perlite Soil mix Assorted small plants, such as ivy, mini-african violets, small herb plants, or cacti Glass or plastic for top What to do: Wash and dry the aquarium. In thin layers, add the charcoal, pebbles, perlite, and soil. Make the soil deep enough to support a small plant, approximately 1 1/2 to 2 inches deep. Water plants well and remove from their containers. With a teaspoon, dig a small hole for the root and plant the herbs, flowers, and small plants. Do not put them too closely together. Now it\u0027s time to go out and find insects. After you collect the insects, put them in your terrarium. Cover the aquarium with a screen top. Place in light, but not direct sun. Water only with droplets since this will be a moist environment. Enjoy watching it grow.