How fast do they grow?

[Guag]

I saw a <1" French Angelfish at the LFS today. Beautiful little fish. I'd never seen one that small.
Anyway, how fast will that little guy grow into a foot long fish? How long before he is 6"?
Is it difficult to feed an angelfish that small given their need for sponge?
Thanks

[Pike]

Poor survivability on ones that size IME.... This is with hand caught specimens (Keys) living in a lfs in a 2K gallon system. Gorgeous fish though...

[tankslave]

max length is 15"
you saw the black and yellow juvinile. They completely change colors as an adult. End up mostly grey-blue.
also not reef recomended.
Most angels should only be kept by experienced hobbyist with a large, well established tank.
I know they're real beautiful, but save yourself the agony.