I have 3/15 plants getting brown spots. I'm using General Oragnics Go Box in 5 gal ebb and flo buckets currently 500 ppm they sprouted 3/5 and pics r from today. Under the lights temp is 78-85F 2x1000 currently flooding 4 times a day. How do I fix this? Is it Bugs? Wind burn? Nute Burn?