Powdery Mildew help!

I've noticed some plants have a couple leaves with Powdery Mildew, I've noticed it for about 2 weeks now, but it has not gotten worse. One plant yellowed up quite a bit, however I'm not sure if this is from the Mildew, or if when I was transitioning from Veg to Flower if I neglected to add enough Nitrogen to the res.

I'm starting to spray the leaves with a formula(Fungus Pharm, anyone used it?) that seems to be working fairly well. I've fixed all the problems causing the mildew to proliferate I think. Added a couple more fans, and I'm not leaving my tent open to the air instead of sealing it up. It's now very dry in my grow tent.

My question is, am I just seeing the beginning of this? All the research I've done online shows pics of leaves and buds completely covered, I've only see the mildew on about 2% of the leaves or less. Should I be freaking out? Or will I probably be okay, as long as I can keep the mildew in check? Or does this crap once it's in the plant pretty much kill it?

My plants have another 3 and half weeks to go for 7 weeks.

Yes, freak out. No, seriously though, post a pic of the "mold" so others can help identify it.

99% of powdery mildew cases I've seen are caused by a lack or no ventillation. Have good air movement - leaves should be trembling a bit.

I'll get some pics here in about an hour. I'm sure it powdery mildew but I'll put up pics anyway.

It's interesting I've only seen it on 4 of my plants, all the rest are fine, are super green with no mildew(all but 4 are the same strain). The 4 plants I keep finding it on are yellow, however even when I do find the mildew it's not very bad at all, and it only covers maybe 5 leaves per plant.

It was definitely caused by poor ventilation, I was keeping my room sealed with a really small fan blowing fresh air in, lesson learned, however since I've added waaaaay more fresh air into the room I've not noticed the mildew as much. I also think the spray is working very well. My Humidity never gets over 50 and my temps hover around 75-85(gets to 85 when I turn on CO2)

i've had PM ravage rooms before. i reccomend picking off and immediatly descarding of any leaves showing any signs of PM. we sprayed something called neem oil and had quite drastic benifits, got it under control quite well. make sure to bleach your room and clean very well in between your next crop, PM can linger on walls and other surfaces.

Get the green cure and follow the direction. The PM will be gone after only one app. Heres the web site:
GreenCure fungicide for curing and preventing powdery mildew, blights, molds and other plant diseases

I've been using Fungus Pharm. It actually sounds like Greencure, it's "organic" and safe for use on edibles.

I completely changed my growing environment, I just keep spraying the plants about every 3 days, with the added air circulation, and lowered humidity I haven't seen any PM at all for the last 6 days! :D