I recently read a discussion on using Easter basket "grass" for the larvae to hatch on. That would provide a lot of extra space, like the excelsior.
Patrick Nabors at Saurian also has a nice media that I never have mold or problems with. A commercial media, as someone else suggested, gives you a steady start while you mess around with finding a good recipe of your own. I don't boil new delicups, just use them as is with no problem. However, anything you recycle should be sterilized, of course.
I start a new culture every couple of days. I don't think that attention to a regular schedule for doing this can be over-emphasized. It never ceases to astound me how much my guys eat--even the tiny imitators and new little leukomelas froglets scarf up an incredible amount.
Saurian
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Patty
Lost River, Idaho
D. auratus blue
D. galactonotus
D. imitator
D. leukomelas
D. pumilio Bastimentos (soon)