ph is a bit high for flowering. in hydroton i flower with a ph of 5.3-5.5. also what are you doing to control your thrip problem and are you sure it is thrips and not aphids? either bug needs to be addressed with Pyrethrum based product and not hot shots no pest strips. no pest strips do not have the chemical to kill thrips or aphids. they are mainly used for spider mites and black flys and gnats. if you still have bugs you should fog your room. doktor doom has a fogger and spray and foxfarm makes a great organic insecticide made with prethrum which is derived from flowers in a spray bottle. bugs sucking out the nitrogen and a bad ph will cause this to happen.