Hydroponic systems are a way to grow plants without the need for soil. A nutrient solution is used to provide nutrients to the plants, either directly to the roots, or to the roots through a growing medium such as vermiculite or perlite. Building your own hydroponic station is an inexpensive way of growing plants indoors. You can use materials around the home to build your station. A gardening center will provide the nutrient solution, as well as the growing medium needed for an automatic watering system. This passive system requires no air pumps or expensive bubbling equipment, and automatically refills as it drains.
Place your piece of foam on the floor and set your container on top of it. Cut around the foam around container as a guide. Remove the container from the foam and cut a small amount away from the edges of the foam so it sits inside, at the top of the container.
Trace around the bottom of the foam cup on the foam and cut out holes to accommodate them. Fit the cups so that they rest toward the lip of the cup. This allows the roots of your plant to rest inside the container. Poke several holes into the bottom of each cup to allow room for the roots to grow.
Cut another hole into the foam so your 2-liter bottle will fit into the hole just past the shoulder of the bottle.
Fill the 2-liter bottle with hydroponic solution and water.
Pour nutrient solution into the container until it is about 1 to 2 inches from the bottom of the cups. Wet the growing medium inside the cups at this time and place them into the foam board and put the board into the container.
Turn your 2-liter bottle over and quickly put it upside down into the hole you cut out of the foam board earlier. Force the bottle until the mouth of the bottle is submerged slightly into the nutrient solution. As the plants use up nutrient solution and the solution level lowers, the 2-liter bottle will drain into the container, no need to refill until the 2-liter bottle is drained.
Place your foam with the cups inserted on top of the container and turn on the air pump to get the nutrient solution moving. Check the nutrient solution regularly to make sure the level is high enough to touch the roots of the plants, which will appear at the bottom of the cups.