I personaly would not go altering anything harf way through a grow let this grow finish then start with organic the next.I have grown organic and to be honest has long has the plants are flushed 1/2 week before the end of the grow most of the nutrients are flushed out any how.Growing organic can be a nightmare you will fine that all organic grow mediums be it soil have far more insect life in them because there organic and the people makeing them dont want to add nothing to the soil[compost].Organic is over rated when it comes to growing cannabis belive me has long has you flush the soil for 2 week before the end of the grow then you will get no chemical taste any how.The yeild will be far lower also if you do go down the organic root.