don't ph anything, you're in soil.. ph'ing to 5.9-6.1 is too low.. ideal ph for soil is 6.5, and you never should adjust ph in soil, its just not necessary.
you're overfeeding them.. soil doesnt need to be watered every day, or fed every day.. the directions on the bottle are for a weekly feed schedule.. meaning thats how much they should get over the course of a week.. so you can feed it full strength all at once, and water only the rest of the week, or divide it up. so yes you're going 1/4 strength.. but watering with it 7 days a week you're really giving it double strength at the end of the week. plus using salts that frequently in soil you're sure gonna get build up..
try watering more when you do water to achieve run off and saturate your soil.. then don't water again until its dry.
a good rule of thumb is when you transplant your plants, pick up the pot with the soil dry to see how much it weighs.. and use that as a reference until you get familiar with it.. cuz even if the soil looks dry, its probably not.
just back off on the feed for a week or so, and water more volume, and less frequently, you'll be fine. a week from now, dose them once a week with 1/4 or half strength.. if they stay green then you're good. if they start to look hungry then the next watering give them another dose of feed.. its easy to feed more, MUCH MUCH harder to undo overfeeding.