Like people, plants require certain elements to survive and thrive. While traditional gardening provides many of the essential elements through the soil, hydroponic gardening supplies nutrients in a liquid solution. You can use this type of garden to grow a variety of plants, including vegetables, herbs and flowers. Many commercial greenhouses use hydroponic gardening techniques to conserve space and control their plants' environments. You can use this same method on a reduced scale to establish a basic hydroponic garden inside your home.
Use a large, waterproof container, such as a 10 or 20-gallon fish tank. Rinse out the inside of the tank with clean water to remove any cleansers or residue. Mix your hydroponic solution with the recommended amount of water and fill your tank with this solution to a level about 2 inches below the upper rim of the tank.
Attach your air stone to your pump with the plastic tubing. Set your air stone in the center of your tank, submerging it in your solution. Place the air pump outside your tank and plug the electrical cord into an outlet. Adjust your rate of airflow until thin streams of bubbles emerge from the air stone. This low setting will provide adequate oxygen to the roots of your plants without churning the water, according to Texas A&M University's Horticulture Department.
Measure the opening in your tank. Subtract an inch from the width and the length and mark the measurements on your piece of Styrofoam sheeting. Cut the piece of plastic foam with a sharp knife. This should fit inside your tank and float on the surface of your liquid solution.
Turn your small pots upside-over your plastic foam sheeting. Space them evenly across your piece of plastic foam and trace circles around the edges of each one. Use your sharp knife to cut just inside your traced circles, making round holes in your plastic foam.
Fill your small pots with a solid substrate. You can purchase a commercial substrate from a hydroponic supplier or use a mixture of small gravel, sand and peat. Leave about 1-inch of space between the top of the substrate and the rims of your pots. Lay two or three seeds over the top of the substrate and cover with a fine layer of peat. Moisten the peat with a few drops of your hydroponic solution.
Insert the small pots into the holes you cut in your piece of plastic foam sheeting. Allow the rims of the pots to remain slightly above the surface of the sheeting. Place the sheeting with the inserted pots on top of the solution in your tank. The sheeting will float on the surface of your solution.
Add to your solution as it evaporates. Remove and replace about half of your solution once each week to keep the hydroponic environment fresh and clean. You can use a fish tank siphon to suck the old solution from the bottom of your tank without disturbing your plants.