The ideal growing temperatures are 21oC - 24oC (lights off) and 24oC -27oC (lights on). These temperatures allow your plants to function at their optimum level
WATER temps should be between 18 and 25 degrees Celsius. thats 64-79 Fahrenheit. The water loses its oxygen holding ability after temps get above 80 and water cooler than 60 is detrimental also. Roots like oxygen, so keep it cool.