Cindy,
Not to hijack this thread, but I'm thinking about getting Columbians, and would like to hear your experiences, and where you got them. You must like them or you wouldn't have gotten a second flock.
Wyandottes are usually slower to start laying than other breeds. Mine didn't start until 33 weeks. Just be patient, and you don't need layer feed, All Flock with oyster shell on the side will work fine.