Depending on the plant’s stretch, your plant may drink more or less. If your plant is lengthy and sativa dominant hybrid, it will probably drink more volume of water. So that means it is probably taking in a lot more nutrients than it should I would recommend diluting your reservoir and lower the EC by 20%.
Burning is not too much of a big deal however if its left unresolved, it can impact your plants development.
I have burns on my plants all the time.