They do look and act like little chubby danios except they stay nearer the substrate.
Mine are almost always amongst the plants in the top 1/8 of the tank, only a few inches below the surface. It's interesting that yours prefer to be deeper.
I also saw them at a LFS recently tagged as "Fireworks Rasbora". I inquired on the different name and the owner said that's how they're listed now (He wouldn't carry them at first because they were so expensive for such a small fish. I really don't blame him). I said, "I see they're down to $3.98. Is the price coming down because of the captive breeding?" He said it wasn't the breeding, that a new, bigger source had been found so they're not under so much demand and that hopefully the risk of going extinct in the wild is gone.
Personally, I don't care how well an animal breeds in captivity, if there's none left in the wild. If I had known that the original source was so tiny, I probably wouldn't have gotten them. Just like I won't support any dyed fish sales.
Let's hope the new source story is true.
Tommy