Hi there Leslie,
Congratulations! TGHese look mightly pleased with you. I would stop putting the hat on during the night. THe plants have rooted and are growing. In another 2 weeks you will see the plants safely continuing on their way up. If they just continue to be happy, you can give them their own pot.
I personally would NOT put them in bonsai soil to start with, unless you plan on doing a shohin style tree. Normal potting soil is much better to beef of the plants. You will get a quicker result, and the plants are easier to take care of.
Feeding? Just treat them as regular house-plants now. Just let them go, and feed as normal. When you think they are big enough to start styling (Which you can now of course already do by removing growing points where you do not want them) you can decide to report into bonsai soil.