Well, someone please correct me if I am wrong, BUT... As far as I know, once a cutting has rooted, it is ready for like 900ppm strength nutes.
The theory behind this is that a clone is essentially the same age as its mother, therefore it is mature enough, once it roots, to take on full nutes.
I have about a 3 week old clone right now that is yellowing at tips and other places and its because I had the ppm at about 500 for a while and its just been begging me for more.
I am myself not super experienced, but this has been my experience so far.
Hope it helps