over complicating things just tap water,no need to ppm/ph if ya from uk waters fine,
mist 2 times a day for 5 days then once a day for 5 days then no misting,just keep the cloneing medium damp,i use a normal house lamp with a cfl bulb in for first 3 days just a lamp with shade of laid n its side near touching the top of propagator lid this will give a bit of warmth.
Then after the 5 days they should be stood up i put them under a 4 tube t 5 they will root in 12/14 days winter 6/7 days summer,yea out side temps do effect the time.in winter leave the lights on 24/7 summer 18/6.
I have took 1000's of clones and the best way i have shown people new to cloneing is ,to take a clone of the plant,hold it at the side of the cube /rockwool,you want the stem to be fully in the rock wool right up to the first set of leaves,this helps the clones from drooping.make sure you pre make a hole with a kebab skewer or cocktail stick.
Most of the people i show how to clone over complicate things,no need all they need is water and the cut put in clone x,for a few seconds.Has soon has you see the roots straight into soil or i put them into bio bizz soil the one with out any feed in,then once there well over root bound in a small cup i put them straight under 600 hps after pre potting in coco/clay balls.
But in most of the grows i do clones are took at week 4 of veg of the plants im going to flower,then they are flowered that way i dont keep a mother.While the plants in the flowering room are doing there thing i do what i said above takeing the clones then once rooted i put them under a t5 for 6 week 2 week for the clones to root and veg for 6 week by this time by the time the plants have flowered the next lot are 2 ft and your ready to flower again,i top the plants at least 4/5 times while there in the t5 room,if you do more than two you will need either more t5's or a 250 hps so they don't end up with the nodes miles apart.but 99.9% of my vegging is done under a t5 and the plants allways throw around 28,dry from two min..........tyke