PPM? For clones Total??

So have read that seedlings and or clones should have about 300 ppm. Does that include the waters starting PPM for a total or 300 ppm plus the starting waters total?

I'm pretty sure it depends on the nutes your are using. I've been told to use half strenght of 1000ppm for my cuttings, so i am watering 1/4" of water at 480ppm in the bottom of the tray when needed. I don't spray them also. It's been fews days now 4 or 5 to lazy to look at the calendar lol.. but they are looking good. Pretty sure some are rooting ...
As for your question, you need to include the water ppm to the nutes... so if you want it to be 300ppm and your water is 120ppm then you want to put 280ppm of nutes... anyway best luck for you buddy.