coco is not like soil there is nothing in the coco that can keep a cutting going,start cutting in a compost,and start on a 1.1 has soon has ya have a few roots.the purple coulour is caused by the lack of nutes start of like i say on 1,1 ec second week 1.2 third week 1,3 fourth 1.4 thats veg.i use coco but all ways get cuttings going in rock wool,then straight into coco once rooted but if im doing clones for next crop then i will put them into something like bio bizz once roots are through cubes till crop done and there ready to go