It's a question you'll probably find different answers to, since there's more than one way to do it. What works well for me (and I've raised literally a few thousand fry of different species, which currently includes geo tapajos red heads) as a starter food is freeze dried brine shrimp. As long as it stays dry it easily crushes up to powder, so even tiny fry, like my rotkeil severums and including my geos, can eat it. In time and as they grow I'll start to add some crushed up NLS or Omega One flake or crushed up pellet, or something like NLS grow, etc. This same basic approach has been successful for me with a pretty good variety of cichlids (including Malawi, SA, and Zaire Blue fronts).
As far as when to start feeding, for most species I wait for them to be more or less free swimming, but typically with a bit of yoke still left to sustain them while they make the transition. Some fish will give you a hint by the fact that even with some yoke left they'll begin picking around for food.
My preference and habit is to raise fry in a decent sized and established tank (as opposed to a tiny bare tank) one that's growing some algae, etc. and I like to have some small bits of driftwood in the tank. The algae and associated microbes growing on driftwood, substrate, etc. is also a source of food that ime many types of fry will take advantage of if it's available.
Don't fry need a bare tank and don't you need to siphon leftover food specks every day or every time you feed? Not in a biologically mature and decent sized tank you don't (I use either a 50 or 55-- and, no, my fry don't get lost or have trouble locating their food). I'm normally running an old Whisper filter on these tanks, filled with poly or filter pad added to or in place of standard cartridges and with a pre-filter sponge over the intake. For very tiny fry I just turn down the flow a bit. In fact, a (trout) study demonstrated that new born fry raised in bare tanks develop smaller brains than tanks with a bit of substrate, pebbles, etc. (see link below) I'm not telling you bare tank is
wrong, just not the way I do it.
http://www.practicalfishkeeping.co.uk/content.php?sid=854
There's other ways people approach it, but that's my method. Relatively simple and has given me good results over the years.
