sounds like a toxic poisoning to me,ph8 will be ok as long as your next water is between 6.5 n 7,the soil is saving your plant mate,plant wants to bud and reproduce,water every 2nd to 3rd day,your ph blocked nuits going into your roots.hope you catch it in time mate,or you'll be forced to pull her coz you mite get an 8th of an oz in the end,plant want to bud,dont mean big ass buds when shes sick