Kevyn,
If you are refering to the white dots in the first pic. as powdery stuff, they are actually trips. You can soak the plant for abt 30 min and gently rub off 'those stuff' off from every leaves. Sorry to say this, you have to throw it away if the plant is heavily infested. That's what I did to mine.
Otherwise, you can use systemic insecticide. Soak the whole plant into the solution. Diluted Malathion solution couldn't kill them. I have friends who use artist paint brush dipped in concentrated malathion and paint at the affected area. Just sharing this info but not highly reccomended. You might KO first before the pest!
Use coarse well draining mix for it's media. MY formula is 50% of crushed charchoal to 30% perlite to 20% of burnt red soil and compost. Most Aec. are highly epiphytic. They grow very slow that way but surely bring out their best colors.
Let me know how well they play then
AT.