Things You'll Need
- 1.5-liter plastic soda bottle
- Scissors
- 6-inch-tall, 1-inch-diameter toilet overflow pipe
- Aquarium pump
- Aquarium hose, 18 inches
- Sponge
- 3 cups coarse sand or gravel
- Drill
- Filter wool
Instructions
Cut 3 inches off the top of a 1.5-liter soda bottle with a pair of scissors. Drill three rows of holes around the top portion of the soda bottle you cut off. Place the cut top into the soda bottle bottom, with the top up.
Push a 6-inch-tall, 1-inch-diameter toilet overflow pipe into the top of the soda bottle. It should be a tight fit. Then, push in aquarium pump airline tubing all the way into the bottle top.
Cut a piece of sponge to secure the tubing in place. Add coarse sand or gravel to the inside of the bottle, around the soda top and tubing, leaving about 3 inches from the open part.
Place filter wool on top of the coarse sand or gravel. Attach the hose to the aquarium pump, and place the sand filter into your fish tank.