Water-based hydroponic systems operate without media. This system requires a continuous flow of both water and nutrient solution. Water-based systems are more compact, allowing a large number of plants to be grown in a smaller space. This system is more complicated to learn, set up and operate than the media-based system. The plants in water-based systems are quickly at risk during mechanical failures or power outages. The plants are supported in a basket with their roots allowed to dangle in the air. Water infused with nutrients circulates through the system, feeding the plants continuously.
Purchase a hydroponic feeding tray or make your own by cutting a piece of 4-inch diameter PVC tubing to a 4-foot length. If you are using PVC, you will need water garden type vented plant pots, 2 inches in diameter.
Drill a 1/2-inch hole at one end of the 4-inch PVC plastic pipe. Place a piece of 1/2- inch wide by 3-inch long piece of PVC plastic pipe into the hole and cement it in so that it sticks up inside the 4-foot tubing about 1/2 inch. Place the tube on a flat surface, such as a board with sides to hold the pipe in place. Simply Hydro recommends the PVC plastic pipe, or feeding tray, have a pitch that is one inch over the 4-foot length to allow the liquid to flow downhill. Make sure the 1/2-inch drain is on the low side.
Clean a 5-gallon bucket, or use anything that will work as a water reservoir. Place a water pump in the bottom of the bucket and attach the airline hose from the water pump to the higher side of the PVC pipe or growing tray. Place the air pump on the outside of the bucket and attach the air hose from it to an air stone. Place the air stone in the bucket.
Fill the bucket with water mixed with the amount of nutrient solution recommended by the manufacturer. Both the water pump and the air pump will need electrical. For safety, use a GFCI outlet. Plug in the air pump and the water pump. Place plants in the pots, making sure the roots hang through the bottom of the pot and dangle in the water. Simply Hydro tells growers to make sure the water is moving properly from the reservoir into the feeding tray and back into the reservoir.