fungus ?

for some reson i keep gettig a little bit of a white powdery like fungus on my leavs & stems. this is in my flower room veg. room is fine. my temp. is 75 to 79 deg. with hum. at 39 45%. when lights r out my exh. fan still runs & my fan that blow on my plants. what can i do to provent this from happening again. thanks for any help.

sounds like you have ideal conditions for fungus.... that sucks

get some fungicide from the garden store really easy...just ask them.."sir i have some

fungus growing on my really large TOMATO plant, what do you have that can prevent this" he should tell you what you need