First hydro autoflower grow -Sweet Skunk

Since last week this plant had grow quite a bit. So much that is drank 3 cups of water in a few days. So I just topped it off a bit with pH water but then noticed it was showing deficiencies in some of the fan leaves. Did a water change a few days ago (2/18) And decided to give it a boost in nutes since is about to transition into flowering stage soon. So far it's doing pretty well. Will keep a close eye with the bump of nutes. Going to start doing rez change every 5 days ish going forward. This plant is getting really thirsty lately and don't want to top off and risk another deficiency.