By supplementing CO2 in the growing area, plants can grow up to 30% faster and produce larger harvests. Until now, managing the CO2 levels accurately required expensive and sometimes difficult to use PPM (parts per million) controllers. How is the new CTC-1 different? The CTC-1 is a CO2 Part Per Million (PPM) meter & controller, with built-in digital temperature control. * Reliable, accurate and easy to use. * Measures 0-2500 PPM and has auto-calibration. * Controls a CO2 generator OR a CO2 regulator. * Temperature and CO2 functions are user selectable. * CO2 levels can either be raised for plant growth OR lowered for mushroom farming, controls up to 15-amps.