Help Sick Plant

hi your plant needs a bit more water, so water until you get run off, also you may want to consider removing some of the lower branches. this will open her up a bit and she will be happier. i know your not over watering since you wait til the soil is dry. you also may want to spray her with just distilled water, spray at lights out, stop spraying when there is improvement, last start using an additive for roots on your plants, like great white or extreme gardening mykos. you want to keep the roots happy for the top to be happy, when you have both your plant will be really happy. hope this helps.