These 2 plants are in ffhf soil , about 7 weeks old. Just barely beginning to flower. Rh has been on low side throughout grow at 40-45%. My issue is with just 1 plant, lower leaves only. Pics show white spots on 3-4 leaves. I checked for bugs, didn't find any. Fed 48 hrs. Ago with 2 tsp. Big bloom, 1 tsp. Cal-mag, 1/2 tsp. Kelp me kelp you, and backing off N with only 1/4 tsp. Wholly Mac. All that in 5 qts. Well water which gave me a tad runoff in 3 gal. Fabric pots. Filling out now and using more water. What do you think is causing the spots ?