well you can get supers from some places in different sizes so you could feed a 30 gram leo small supers, maybe mediums. If you get the lrage supers Id wait til 50 grams thsoe are really big
I buy supers 500 or 1000 at a time. If I order the "medium" ones, I get a variety of small, medium, and very small. The smallest ones are fine for baby geckos. I've started leos on supers w/ no problems.