when you stick finger into soil and it's dry 4-6 inch depth fully water your plant soke! then should be a every other day water cycle. Yes plants got a K2O and p2O5 deffency you should ither goto a hydroponics shop and get a 0-5-4 / or goto a garden store and look around the flowers and tomatos section and look on the nutrishion get something with some K2O and P2O5 and lil MG should be good. For Soil give it nutrishion then wait a week the other water time just use normal water i'd give it another light treatment after that week of normal water see how shes doing then.