This is probably a dumb question but what exactly is the point of using a ballast? Why do you need one? Does a 400 watt ballast go with a 400 watt light and so on...? what will happen if i dont use a ballast?
Need a ballast to ignite and run the bulb. 400 watt bulb for a 400 watt ballast. But you also need the same type of 400 watt ballast such as Metal Halide, High Pressure Sodium, or Mercury Vapor (which is not used in growing plants)