Iknow this will sound crazy but the best way to make a clone grow roots is tough love. I learned this from a old grower if you foliar feed your clones they drink that water screw that if they want a drink they will grow roots. Thats what roots are madr for, if a clone thinks its going to die its only natural for it to do everything it can to survive. i never use a dome or foliar feed and i get 99% clone rate.heres what i do
1 i only use clonex products alwasys has worked 4 me
2 soak rockwool overnite in clonex @ 5.1 ph
3 take rockwool out and shake a bit just a little, u do not want it water logged
4 new razor blade cleaned with iso ,45 deg cuts dip in clonex gel a.s.a.p
5 put clones in rockwool and put under flouro in room 70-75 deg.
6 wait until rockwool is almost dry about 4-5 days mix sol of clonex @ 5.8 ph in small container dip rockwool cube by hand only letting the bottom third of the cube to get wet. this will tease the plant and poof roots!! remember you have to keep dipping rockwool every 2 days or so do not let get bone dry at 8-9 days check 4 roots goodluck