DWC Green Poison

Everything was going too well. She makes today 6 weeks. Wanted to flower her soon. Last Saturday found her very droopy. I also have a auto in dirt that use some hours of light in the hps and she is also not very well so i think is environmental. We had a cold polar front and temperatures dropped a lot. 20ºC lights on 16ºC lights off trying to keep watertemp at 20ºC more or less (had to add a aquarium heater.) I added a graph from my simple arduino monitor and not very much changed this week. This may be: Low temps (added aquarium heater and turned the fan off at night time and 15m on and 1 off with hps on) Air problems (because of cold the house is closed more) Too much nutres (i made last solution with 16ml and today with 12ml) Light problem (transition from the leds to the hps dialed at 250w and now lifted the light more) I think i also have some very small thrips in them but with very little damage. If anyone can help i am very grateful...