need info

HI, what are the ideal temps for lights and lights off. the temp in my grow room drops by about 20c when off from 80-85 to 60. my leaves are starting to grow differently at the start they had at least five leaves on each stem, now im only getting three and sometimes a single leaf. also the stems are purple. is this due to my temps please help a budding novice. my plant is in a dwc buubler in beside soil. the soil plants are fine just a bit slow to flower.

75*f off , 85*f on. The colder temps will cause purple. Im sure its prolly ok. Are you budding? lol. It may be the breed or that the plant is weak, my blueberry plant likes to just throw 3 leaves. After 18" or so it starts making 5 leaves.

sure am and its slow from what my lacking knowledge tells me. i think i need to turn rthe heat up. cheers