Flush all your plants with a ph of around 5.5 nothing in it just water do this 3/4 times till water till water is running through soil.Looks like you have a potasium def lower feed for a while a week or so use harf strenth but don't start feeding till they have dried through good and propper.Not sure about the one with redish coulour in the leaves the 3rd set of pictures alon bottom left hand corner but givein the plants a flus about every 3 week stops all this shit happening i know its a pain but its well worth it.