hey there, sulfur is good but only really used during the flowering, magnesium is important throughout but it doesnt relate to the N in any way, more like it regulates NPK in general as well as its important in photosynthesis, so it's more sensitive to the amount of daylight hours than to the NPK as well as it becomes important at different stages of the plants growth for example during stretch periods. so to answer your question, your PPM is spot on but you can lower it with no problem by using less mgsufur and more epsom salt. Hope this helps ! 🚀