Magnetic Ballasts have been around for years and are loved by gardeners from around the world as they are inexpensive to buy. A Magnetic Ballast contains a core made out of steel plates wrapped in a copper wire coil. As a result, this helps create a magnetic field which regulates the initial electrical current delivered to voltage-sensitive light bulbs. Because of this regulation, they emit a lower intensity output, meaning that light bulbs have a longer lifespan. In addition, another benefit of using a Magnetic Ballast is that they don’t produce any radio interference. This is especially good if you are using a wireless nutrient monitoring system.