Springtail bug in roots good or bad?

They are nitrogen fixing ( the springtails) at least from what I have found when researching them. So it is either is a coincidence that my plants show sign of nitrogen toxicity with the burnt tips and eventually burn sides,or that I experimented with these plants to only use 1 gallon pots the whole time. I read a lot about it and the internet says yeah it's fine so long as fertigate(water with nutrients I think) at least twice a day. With others saying no it's the worst idea. So I decided to find out myself the truth. At week 5 of flower in I started seeing the burnt tips so I cut the canna BioFlora at a NPK of 2-2-5 ,and the biocanna bioboost supplement at 0-1-0 for the NPK, in half. Then I ran a Cyco Platinum nutrient Kleanse formula. I saw no slowing of the problem so I cut the levels of nutrients in half again. And so on. The only thing that is wrong with the plants are the tips. Not the D's thankfully. I water them by hand 2 or 3 times a day at almost 2 liters each. My only guess is that there is too much nitrogen. So I cut the BioFlora entirely, and use just the bioboost. It doesn't seem like it will harm much. They only have another 3 weeks until harvest. But could springtails really create so much nitrogen? Or is it the small 1 gallon container? Thank you all for reading. I am just curious that's some bug I've never seen before in canna's Coco coir, and black gold perlite. That I have used for a while. Just makes me think that's the origin. But who knows. Not me. Thanks again.

Me personally I don't want any critters in my plants or substrate. Would try to eliminate them to be safe. Good luck and happy growing 🌱