I had the same problem with my NL from marijuana-seeds.nl. It turned out to be a ph issue. I was putting in 6.5 water but my runnoff ph was 7.8. Once I got my runoff down to 6.5 the plants recovered quickly and budded like monsters.
And remember that your fan leaves are not going to heal themselves--the plant finds it easier to grow new fans than heal sick ones. Once yellow and dried out, they'll stay that way. Luck.
Another question, how long into flowering does a male plant become dangerous for your crop. I know as soon as your sure their males. But im unsure about a couple. Do the flowers get real big before spreading polin?
You don't need to be afraid of them...They're not dangerous. If you don't want to make seeds you just pull them as soon as you start seeing balls. If I were you I would take some of the pollen from one of your best males and put it on one of your females to make some seeds. This way you don't have to buy seeds for this type of strain. Here's a link to sex ed for your plants. http://www.marijuanapassion.com/forum/showthread.php?t=16565
If you want to make seeds, just get some pollen from the male you want to breed with a female and later sprinkle pollen on the females buds. You want to separate the female from the others when pollinating. Pollinate the plant with a clean paint brush, q-tip etc... After pollinating the female you spray her down with water so you keep the pollen on her only. Leave the female away from the others for at least a couple hours before placing back in the grow room. You need to make sure you pollinate your female early into flower so your seeds have time to mature. It takes around 4-5 weeks for your seeds to mature.