dark damp and moldy help!!!!

I switched to flower about 3 weeks ago and now amstarting to see some mold growing in the corners and along the bottom of the walls. The humidity is between 45-70,i have a little cheepo dehumidifier i got of e-gay for like 40 buck it pulls about a pint of water out every 24 hours. The mold is only growing in areas that dont get that much light during the day, like behind the res. and shit like that. how do i get rid of this? I think i have plenty of vetalation with a vortex 640cfm exhaust @15 min per hour and a 300 cfm intake running with it,one islating fan blowing between the light and plants and a smaller one blown at the bases of the plant.HELP me out I don want moldy buds

anyone? how do i get rid of this shit???

spray back there with blrach water. and your humid. is way to high for flower. you want in the 30% and lower if you can. get that down and you willbe good to go. good luck

i thought hum should be around 40-60. Anyone know a place to get a dehum. cheep