It's Hydroponics This is Blue Kush Indoors She is right about 5-6 weeks Two 180W LEDs The lights were about 8 inches and I just bumped them up to 14" I refill the water when it is about 2 inches below the bottom of the net pot and fill it up to about a quarter of an inch from the bottom I feed them Advanced Nutrients Micro, Bloom, and Grow, 8ml per Gallon plus 4ml Per Gallon of Cal-Mag, and per five gallons a scoop of great white. I usually have her at 5.5 when I top her off and she usually drifts up to about 6.0 The temp might actually be the issue as it's just under 90 degrees at the peak 10 Gallon pots They are tents, inside a closet, inside my home, so I doubt there is any bug issues. I think that should be about all you need to know. I have had this issue in the past and I am pretty sure it's heat related but that could just be coincidental.
Looks like nute burn to me. What strength nutes are you using? It should not be greater than 1/4 strength at 5-6 weeks. Also you want the pH at 5.8, 5.5 is too low.
Well it only sits at 5.5 for about a day, but I usually never shoot that low, that's just the lowest it drifts. I thought hydro you work your way up to 1/2 strength? My PPM is around 900