Flush before you add anything ... Agree that you should have a source of Cal-Mag, as your tap water/filtered water prob doesn't have enough. And I know you said you're in distilled now. Is that something you JUST did to flush? Or do you always buy or make your own distilled water? The reason I ask, is distilled takes out all the micronutrients that are usually in normal spring water. It's great to get filtered as you want no lead and very little chlorine getting into your plants. But distilled will create defeciencies in your plant as it has nothing. And if you do not have some sort of supplement to make sure your plant has the entire nutrient array within it's soil/hydro medium/nutrient stores (leaves/stem/stalk).
The problem with burns, is that it does much more damage to the plant and takes much longer to recover from than a simple defeciency. At your stage of growth, you will see defeciencies slowly appear and can keep an eye on it day to day and catch on quick. But a burn will show within a day or so of a feed that is too strong. So if you feed your plants one day or up the NUTE level in your reservoir (and don't forget, most nutes if they aren't PH balanced WILL throw your PH off which can seriously effect plant health & nutrient uptake), and see burns the next day, it should be pretty obvious to you that you've just experienced nutrient burn. If your plants look healthy for a week and you haven't fed anything too strong, or maybe nothing at all, and then they start to look unhealthy, then yes it is a defeciency and you'll know that and can step in to correct it before it becomes any threat.
In most cases, defeciencies only slow down growth and if corrected soon enough, it's barely even noticable. A burn can stunt & slow your growth down a few days to a few weeks, or even longer if not corrected by then. Then the overall appearance of the plant doesn't look healthy and takes a while to recover. And don't forget about the unwanted STRESS to your girls. You are supposed to pamper them, give them everything they want (in moderation, of course), and literally just do what you can to put them on Cloud 9. If you stress, you are now increasing chances of MALES, HERMAPHRODITIES, SEEDS/BANANAS, AND/OR LOWER YIELD/POTENCY.
Once you have your plants back to normal health, again, start @ 1/4 strength recommended dose of whatever you are using. If you're feeding 4-5 gallons and it says add 1-2ML/gal for a total of 4-10ML, then cut that down to 1-2.5ML. It may look like nothing. But nutes are highly concentrated, so it IS PLENTY.
Make sure in Veg you have a good formula with proper ratios. 10-10-10 or 6-12-5 are not ideal ratios. You want something high in Nitrogen, low in Phosphorus, and somewhat low-medium levels of Potassium. Any complete formulas you can find that already have trace amounts of Zinc, Iron, Magnesium, Calcium, Boron, Vitamin B complex, and more ... are going to be even better, as you won't have to find seperate formulas to add along with your macro if it already has it. Although, it is nice to have products for each main element you feed your plant, as you can find your plant may be in ideal ranges for all nutes but one. So if you feed something specific, it can fix that and leave everything else ideal. Whereas, if you use a macro feed to try and fix one defeciency, it can now throw all the other levels that were once ideal into ranges that are now too high.
Hope all this helps brotha!
