8-10 inches does sound awfully close to a 1kw HID light. I grew a few blueberries and they are finicky (at first--then later love nutes)but the problem I had with them was overfert--nitrogen in my case which made them a beautiful color very unlike the ones in your photo. Hope you get to the bottom of it. good luck
Weedhound Reviewed by Weedhound on . light stress ??? help n opinions welcome hello all , lil help cyclonite or others , lil background = in wtrfarms , room temp =73deg. , rh = 55% , ph = 6.0 , water in res n cells =65deg. , g/h 3 pt. nutes = ppm of 420-500 . 3 blueberry / 1 cotton candy x nycd . they just got their first taste of nutes n jumped like 4in. overnight . got like w/in 8-10in. of 1000w/ hps in cooltube . largest leaves on blueberry were affected the worst , tips not curled like nute burn , looks like light or heat stress i think ? cotton candy x Rating: 5