By 'nls' you mean New Life Spectrum fish food? If so, what type are you feeding them?
I ask, because I brought some galaxy rasboras back from anaheim with me a few weeks back. They eat flake food, but mine seem kind of finicky when it comes to eating. It would be nice to know what you are having success with as I see lots of NLS foods that I could try... Small Fish Formula, Community Fish Formula or Finicky Fish Formula would all be good candidates.
The store I purchased them from were feeding flake and baby brine shrimp.