people are very (VERY) lazy... you'll have to figure out how to add more pics directly to this journal as attachments to get more feedback 
you've got some different issues with your plants... the best investment you can make is a pH meter and a ppm meter. (especially the pH meter) until you do, i'd recomend only using store-bought Reverse Osmosis water.
i looked at the pic but i've never had 'white powdery mildew' but i can only guess thats the problem that you were just asking about. you mentioned horrible humidity in your area. thats all it takes. you'll need to either get lots of airflow into the room (oscillating fan and a good exhaust fan) or a dehumidifier. you need to arrest the development where its at though. neem oil might do the trick... or some 3 percent H2O2 mixed like 1 or 2 tablespoons per gallon of water as a foliar spray / drench / wipe the junk off. i'm no expert on mildew so do some further research on remedies for that. Another thing that is priceless ($7-9 dollars at Walmart) is a small digital temperature and humidity gage. They look like oven timers... but they give you the current, as well as the high and the low, for both temp. and humidity. temp's 90 and below are fine... humidity you want to keep below 60 percent - especially during flowering.
having some leaves in poor health toward the bottom of the plant isn't the end of the world ... especially since the 250w won't have a lot of penetration ... and you said that overall the plants are growing very nicely. there's a thread on here of 'how to post big pics' in your posts... ur pics aren't huge, but it'd be nice to work them right into the text so people can see what ur talking about.
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you've got some different issues with your plants... the best investment you can make is a pH meter and a ppm meter. (especially the pH meter) until you do, i'd recomend only using store-bought Reverse Osmosis water.
i looked at the pic but i've never had 'white powdery mildew' but i can only guess thats the problem that you were just asking about. you mentioned horrible humidity in your area. thats all it takes. you'll need to either get lots of airflow into the room (oscillating fan and a good exhaust fan) or a dehumidifier. you need to arrest the development where its at though. neem oil might do the trick... or some 3 percent H2O2 mixed like 1 or 2 tablespoons per gallon of water as a foliar spray / drench / wipe the junk off. i'm no expert on mildew so do some further research on remedies for that. Another thing that is priceless ($7-9 dollars at Walmart) is a small digital temperature and humidity gage. They look like oven timers... but they give you the current, as well as the high and the low, for both temp. and humidity. temp's 90 and below are fine... humidity you want to keep below 60 percent - especially during flowering.
having some leaves in poor health toward the bottom of the plant isn't the end of the world ... especially since the 250w won't have a lot of penetration ... and you said that overall the plants are growing very nicely. there's a thread on here of 'how to post big pics' in your posts... ur pics aren't huge, but it'd be nice to work them right into the text so people can see what ur talking about.
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