What type of medium; soil What brand and type of soil: FFOF Indoors or outdoors? Indoor What strain? Lowryder How old are the plants? 41 days What type of lights and how many watts? cfl 700ish How far from the lights? varies What, how much and when was it fed? NPK? Molasses, FF Grow Big, Tiger Bloom, Big Bloom What is the medium/runoff pH? unknown What are the temps and humidity in the room? 85F 28% What size pots? 10in pot
Definately got some nute burn going on. Flush the plants with clean water, let them dry for a day or two and start back with nutes at 1/4 strength. Sounds like you are giving them good quality nutes, they just got overloaded in the nitrogen department. The flush should take care of that. As far as the little gnats go, they tend to appear when the soil is allowed to stay wet. If you let the plants dry out another day between waterings, you will find they disappear. Dropping the temp down to the low 80's/high 70's would help too.