Hey,
Honestly i would be willing to be that "your frined" is overwatering them. Despite what you think i almost guarantee that is the problem. If not, it has to do with over nutes. If you are POSITIVE it cant be from too much water, flush the plants and give them strait water (no nutes). By the way, if you honestly think that people are watching your emails that would want to bust you than you are honestly retarded. The only people that can do that is the federal gov't and unless your growing huge crops of weed i doubt they could really care less.
Watering prob over or under water.
Water like this, like nature. Thoroughly saturate the soil then wait up to a week until the soil is dry, you can tell by eye, by weight or, by the finger method. Then water thoroughly again, by thoroughly i mean 10-20% run off water. Just like in nature, it rains hard, then its dry for a while.
You can tell when soil is dry by eye is when the soil is starting to turn grey, but in a low humidity / high circulation this doesn't work as well.
You can also pick up the pots after watering and "feel" the weight. then when its completely dry pick it up and weigh it again. This is my preferred method of watering.
Also You can stick your finger in the soil all the way. And if its dry at your second knuckle its time to water. Lamp.