Krib fry are easy when it comes to feeding. I've used Hikari First Bites in the past and that worked fine. Mix it with a bit of tank water in a glass and then use a turkey baster or something to drop the mix near the cloud of fry and they'll happily go for it. The bigger problem might be to deal with the aggression level that you're likely to get in a community tank. Adult kribs are typically well behaved in a community tank... until they have fry around. Then they get nasty. If you have other fish in there that can take on the parents, then the fry will likely be eaten. If you don't, then the parents will likely terrorise the other tank inhabitants. I know, I probably sound a bit pessimistic here, and I sure hope that things work out more easily for you. But for me I've always found it easier to isolate the parents before the spawn, or siphon out the fry and raise them in a separate tank. The latter option gave me the greatest survival rate for the fry, but the problem with it is that you don't get to admire the great parental display of the parents...
Good luck. Kribs are great.