flushing is always a good idea, the water cure basically gets rid of the by products of photosynthesis which give off that burn leaves smells but it wont truly help getting rid of the nutrients if they are in excess. The main thing during the water cure is to change the water quite frequently (4 times a day or more if you can!) because the water gets saturated quite quickly actually. Plus if you change the water more frequently the cure could last less long, you'll be done in 2/3 days ! the main difference between the photosynthesis chemicals and the nutrients is that the photosynthesis chemicals are more water soluble than the basically insoluble organic nitrates aka "the nutes". hope this helps my friend ! 🚀