The first one, as the name denotes does not employ a solid medium for the roots, uses only the nutrient solution. Whereas the second system possess a solid medium for the roots rather than any solution and is mentioned according to nature of medium, e.g., sand culture, gravel culture, or Rockwool culture. The best advantages of using soil-less cultivation of plants are, first and foremost it produces much higher crop yields and secondly it can be used in places where in-ground farming is not feasible.
The major reasons to adapt hydroponic systems are as:
It does not require soil.
The water stays in the system and can be reused - thus, lower water costs.
As the nutrient enriched water stays in system, lower nutrition costs.
Nutrition does not escape into the environment because of the controlled system.
Constant and high products.
Chances to vermin and bugs are easier to reduce.
With all above benefits, the most important thing in hydroponic system that is required for plant's and herb's growth is light. In order to grow plants indoor, it is required to provide with light similar to what they would get outside in the sun. Grow lights are tremendously significant for any inside farming system. The natural light that sun provides is difficult to attain with the artificial one indoors, but still effects are there to stimulate plant growth.
While preparing for enclosed lighting system the important thing to be careful in choosing the light spectrum frequency of the bulbs you use as different spectrum have different effects on a plants growth. The main light bulb types that are used in grow rooms are fluorescent grow lights, HID lights which include high pressure sodium lights and metal halide lights, and led grow lights. these lights can be used either alone or in combination, depending on the constraint.