Problem on leaves progressing please help

The plant is in its 2nd week of flowering and is being grown in soil. I used FF nutrients for veg and itt is watered using a brita purifier with molassus and has been fed with kool bloom once since being flowered. Since flowering began, i noticed brown spots on the leaves and it seems to be spreading from the lower fan leaves up. The brown spots appear on the edges of the leaves and sometimes spots on them. I stopped giving the plants molassus when I saw the spots, and it seems to be getting worse. What should i do? is it possible that it's blights? under-feeding/over-feeding?

Please help and let me know what can help save this plant.

Should i spray the leaves with koool bloom?

No you do not want to foliar feed during flowering, at least I would never think about it. If you're in soil then feed via soil watering. I have had plants experience that type of look before in flowering but never turned up to be an issue. If it's not spotted all over your plant I wouldn't worry about it...however if it is getting worse everyday, might need to take a trip to the hydro store.

what exactly would fix the problem?

What is the pH of the water you give it? That might help to figure out what the problem is and/or stop future problems from happening. You should be watering with pH 6.5-6.8 water, and measuring it after you add in any nutrients or supplements.

You can foliar feed once if need be in flowering, some peope do it during flower everyday, and stop 2-4 weeks before harvest, to prevent mold.