Oh My God..I see why ur plants started a huge argument in the other thread.
go to walmart right now and get some miracle gro potting mix.
-replant ASAP-
make sure the soil has plent of "little white balls" (perlite) in it so the roots can breath.
but please, whatever you do, for the sake of your plants get some new soil.
Any YES on the Humidity dome (ziploc bag) idea, clones are supposed to have 100% humidity until they root.
and what is ur light schedule? 24/0 I hope, with those temps it would be best to run the lights 24/0 and turn all fans off.
and yes on clipping the tips of the leaves on the clone, it promotes growth to other areas of the plant when u clip the ends of the leaves.
hopes this helps, plz respond asap