all 3 are under a 400w hps light,,they are 3 weeks old on 18hr cycle..daytime temp ranges between 24-27c, humidity between 50-60..nightime the temp ranges between 19-24c,humidity between 60- 87..i have a heater fan in there dat helps control humidity at night or it could shoot up to 90!..the humidity goes to up 80or so then fan kicks in to bring it back to 60,fan turns off,humidity gradually goes bak up to 80 then the fan kicks in again..could this be bad for the plants? i think this is the reason for the leafs drooping..any ideas? and the marks on the other plant what are they?? also if you look close the bottom leafs on the plant in the middle are turning bright yellow?.. and there all 3 are geting the same grow mix from seed.. 
