Still having plant problems

I posted some pics a few weeks ago, and had a few great anwsers. I am debating to flush it or use epsom salt? I have heard some bad things about epsom salt and saying don't do it. I think it is a magnesium problem. I have raised the ph level closer to 6.5 or so. The plants are AK47 (65% sativa, 35% indica). The yellowing and browning are moving up to the top of the plant. I have only two plants, and only one is affected. Why would this be? I received them from a friend that were ready for flowering. The pics kinda suck, due to being under the sodium light. I know these plants are too big for my cabinet that I have. It is a 400 watt DWC system. I am using GH bloom and using 1.5 tsp per gallon, and using 2 gallons of water about every 4 days. The pics are more yellow, due to being under the hps light. Any suggestions? Flush? I am suppose to harvest on the April 15th. Will they last this long?

might be over watering bro hard to tell from the pics but try letting the soil before watering!

What are the temps? Pics in normal light, including top, bottom, worst leaves and whole plant shots, would help. You almost certainly have at least two problems. If the temps are fine then it's probably Phosphorus & Potassium deficiencies. K def. causes yellowing on leaf margins and downward curling, while P def. causes splotches of brown, crispy necrosis and upward/irregular curling. The two together during flowering often cause brown crispyness on leaf margins. What's the makeup of your substrate? You say that you raised the pH to 6.5 or so. Regular soil normally needs pH 6.5 and if you're using regular soil, it may have been too acidic before you fixed it. What was the pH before and how are you testing it? It doesn't look like simply a pH problem but that could be one of the 2+ problems.