Aquariums can be used as more than a home for your fish. They also can be made into terrariums. A terrarium is a self-contained environment for plants and small animals. They can vary in complexity from simple soda bottles to more complex large glass aquariums. If you have a glass aquarium terrarium and are looking for a unique way to modify it, consider building a waterfall inside.
Insert a plastic bowl or container into the bottom of the aquarium, lining up the top edge of the bowl even with the top layer of soil. The bowl should be approximately 2 inches deep. This is the receptacle that your waterfall flows into, so choose a location near the side of the aquarium where you plan to put the waterfall.
Place a layer of stones into the plastic bowl. Use a variety of stones in different colours and sizes for a more realistic look. Place the bottom of your water pump into the stones. However, make sure the stones will not be blocking the flow of water up the pump. Adjust the placement as necessary. The pump should rest close to the wall of the aquarium. Run the electric cord for the pump up the wall of the aquarium and out the top.
Create a rock surface for water to flow down. Stack stones of different colours and sizes up the side of the aquarium, around the water pump. Apply caulk to the stones to hold them in place. Allow the caulk to completely dry before proceeding.
Add water to your bowl. The amount of water depends on the bowl you chose as well as your water pump. Add water as necessary until you get a good steady flow from your water pump.
Water pumps can be found at pet supply stores as well as craft stores and hobby shops. The model will determine the cost. Test the water pump before you install it. Insert the pump into a bowl of water and turn it on according to the manufacture's instructions. Make sure the pump works and also use this time to determine the flow of water you need. Adjust the water flow as necessary.