I believe flushing should be part of the final phase, no matter what medium you use to grow. Im no expert, i have read a lot information and talked to a lot of people. Experience thru trial and error has been my best educator. I love growing. I will help with any question, if I have the answer, cuz chances are I have or have had the same question. Thanks for your question and your posts, I love reading anything that will make me a better grower. If you post anymore questions, I will try to answer them when and if I can. Thanks :jointsmile: