A photobioreactor for use in a modular system of photobioreactors for algae farming characterized in that the photobioreactor comprises: a structure comprising at least one tubular section for containing the algae cultivation, LED-type lights and reflector bodies that are arranged to reflect the light from the LED-type lighting and transmit it to the tubular section in which the cultivation of algae is disposed, passing through a side wall of said tubular section, supply nozzles located at the base of said tubular section , a CO 2 supply line , a nutrient supply line and a temperature conditioned water supply line , which are distributed near and along the route of the tubular section , which are connected to said supply nozzles , and are equipped with flow valves, at least one nutrient sensor arranged to detect the need to incorporate nutrients, at least one CO 2 sensor and at least one temperature sensor arranged to detect the need to raise or lower the water temperature, and a control unit, which is arranged to receive signals from the sensors and which is arranged to automatically operate the flow valves of the supply lines for supplying an additional amount of CO 2 , nutrients or temperature conditioned water to said tubular section , according to the needs of the cultivation process in view of the signals detected by the sensors, wherein the control unit has means for controlling the activation of the LED-type lights , wherein each LED-type light comprises two types of LED, with two different spectra, and wherein the control unit is arranged to control the two types of LED, so that it regulates which spectrum should be active at all times and in the most appropriate section of the photobioreactor, to promote the growth of algae according to their colour. a structure comprising at least one tubular section for containing the algae cultivation, LED-type lights and reflector bodies that are arranged to reflect the light from the LED-type lighting and transmit it to the tubular section in which the cultivation of algae is disposed, passing through a side wall of said tubular section, supply nozzles located at the base of said tubular section , a CO 2 supply line , a nutrient supply line and a temperature conditioned water supply line , which are distributed near and along the route of the tubular section , which are connected to said supply nozzles , and are equipped with flow valves, at least one nutrient sensor arranged to detect the need to incorporate nutrients, at least one CO 2 sensor and at least one temperature sensor arranged to detect the need to raise or lower the water temperature, and a control unit, which is arranged to receive signals from the sensors and which is arranged to automatically operate the flow valves of the supply lines for supplying an additional amount of CO 2 , nutrients or temperature conditioned water to said tubular section , according to the needs of the cultivation process in view of the signals detected by the sensors, wherein the control unit has means for controlling the activation of the LED-type lights , wherein each LED-type light comprises two types of LED, with two different spectra, and wherein the control unit is arranged to control the two types of LED, so that it regulates which spectrum should be active at all times and in the most appropriate section of the photobioreactor, to promote the growth of algae according to their colour. <EOS>