ive only talked to one LFS about exchanging my krib fry for store credit, and they told me they wanted them to be at least an inch long and that they may give me $1.50-2.00 apiece for them. my first successful clutch is now approaching this size, a couple are actually well over an inch.
my experience with kribs has been this:
2 pair in my 55g community tank didnt work. the dominant pair were ruthless to the sub pair, so i gave the dom pair away.
once the fry get so big, or when the parents spawn again, the female turns on the existing fry as if they were other fish. the male actually protected the fry alot longer than the female, but he eventually turned on them as well.
its taken me a while to get a grow-out tank set up, and as a result, i believe i have a mixture of 3 to 4 spawns currently in there, none of which is being tended by the parents. this over- crowding has had an impact on their spawning and behavior, i believe. they havent shown spawning behavior in quite some time(just the last day or so this has changed) and they appear to be alot more tolerant of the rest of the tank coming around the nest. ive spent the last couple of days removing babies and i suspect once they are gone, the spawning will resume. im not an expert on these fish, but a good source of info is at
www.thekrib.com
i believe its pronounced "crib-n-sis" but i may be wrong.