Arhhh , ok mate sound
like i say im no epert in hydro , but i think you need to lower your ph to around 5.8 and your Ec seems high for the size of the plant ,
id say flush the coco then start feeding at a lower ec at a ph of 5.8 ish ,
hopfully somone who grows in coco will be along soon and should be able to help more or correct me
hope you get sorted bud , oh one last thing i believe coco is very finiky with watering schedules ,it might pay to resarch into it .
all the best
stickyrussian