Nutrient burn

It does look like a bit of burn, I would not say it is advanced or severe, it is light and can be controlled very easily. Its on the top leaves so that means the plant is drinking lots as this is where its happening. It is best to have a EC pen to help determine the concentration of the feed you using. doing this blind is a bit harder but not impossible. If you have a EC pen, mix your nutrients like you have been doing then dilute them down to the desired EC and PH adjust if needed. Should you be without a EC pen, try getting a good amount of runoff on your next feed and reduce the amount that your feeding it but increase the volume. This will act as a mini flush to help correct the issue. Eg, if you are adding 3ml feed for every 1L and you make 4L of feed, switch it up to 1.5ml for every 1L and make up to 8L of feed, then "slowly" water this in and allow the runoff to be waste down the drain. Key word slowly. If you do this to fast it can compact the medium and the water will not get into all the spots to help rinse out the extra buildup inside the medium. After all this monitor the plants symptoms and confirm its not advancing, if it is, you'll need to do more things, Once the damage is done and the tips are dead, they will no come back they will stay that way. Best to also make a full diary as one week on the 3rd is not enough information or details. I'm sure our aware but these are their feed chats and they list light medium and heavy feedings, Buddy of mine used the maxi series and said he likes it, but I think they tweak theirs a bit. https://generalhydroponics.com/resources/maxiseries-feedcharts/ Good Luck!

Nope Thats the nitrogen leaving your soil the soil and the roots system hava a big need of nitrogen in this stage of flowering but u don’t get to worry and add nitrogen In fact, you have to go hand down until you get to remove it by arriving at the flush or even the simple irrigation with only water and finally cut it down this frosty budz

It's hard to tell because you don't have your ppm listed or amount of nutrients you're giving but it could be slight nutrient burn from the look of it, most likely deficient and needs more nutrients. What are you feeding and how much? In the beginning of bloom the plant requires a lot of NPK so be sure you have enough to meet it's needs.

Hello my friend, this is indeed a nutrient burn and a pretty advanced one. To prevent further nutrient burning you can flush the soil with pH 6.5 water without nutrients. You need to use the same amount as your pot volume. So if you use a 10 liter pot then you use 10 liter water. The runoff will flush away build up salts and nutrients inside the soil. Let the soil dry till the top layer is completely dry. After you have done this you can continue feeding with 50% from the nutrients that you gave before. This should be enough!