What's the specifics? Temp, lighting, PPM, PH, soil/ hydro... Those kinds of things will help pinpoint much more accurate than that picture. They don't look half bad though...
i actually pretty much cut all nutes out the last two waterings. i also was giving them half strength nutes so i almost feel like it could be somthing else? my ph is at 6.1 i thought it was that i guess it still could be?