Yellow tips near bud sites

This isn't light damage, so get that back where it was. maintaining DLI is important. nutrient related but more than one thing can cause what you see. "tea" is more about maintinaing microbes, eh? Probably doesn't have much nutrients in it? would need more info there (rhetorical, you can apply some deductive reasoing here and adjust foro what is said below) if it doesn't progress much, it's less of a concern, but if it continues to go downhill you have to adjust the balance of your fertilization, and hopefully it's not the contents of the soil (like amendments that slowly release, because those aren't going anywhere without a stressful flush, which should be avoided as best possible). since you are not fertilizing much, this is about the long-term effects of your soil constitution. You can't do anything about that until the next batch of soil you mix up. Based on description i'd lean toward deficiency before toxicity -- deep into grow and minimally fertilizng, so if it was a toxicity caused by pre-amended soil it would have showed up much sooner. since it's about something you can't really measure midstream, i'd wait for more clear symptoms to confidently diagnose the issue. If it stays limited and doesn't progress, i wouldn't worry too much about it... if you have a guesstimate, be very conservative in your adjustment.. doing the wrong thing potentially makes it worse. put your toe in to test the water and if it works you have a better idea of how to adjust your soil constitution next time.