You need to read the directions for your nutes. I had to flush today and i use FoxFarm hydro nutes. FoxFarm said to flush with 1/4 strength Big Bloom nutes and a Flushing agent and pH adjusted water. So i used Flora Clean flushing agent with the Big Bloom nuts and pH adjusted 5.8 distilled water. My plants have responded well. I believe that you can just use pH adjusted water as well but i just did what FoxFarm recommended.