Tropicallvr

If you are germinating them outside in a community pot, then I just leave them ther until they have a few leafs, depending on how packed together they are. If they are inside in a no, or low light situation then I'd transplant them as soon as the grow above the soil.
For the E.perrieri, don't use the baggy method(uncovered pot in hot/warm spot), and extra perlite or pumice should be a good mix. If you miss a few seed waterings that species may actually thank you and sprout.