I keep the angelfish until they are between 8 and 10 weeks old. By that time, their fins are tall and carried erect; they are stronger and more resistant to moving to new water and new tanks; and they've had a chance to get to know humans as beings who bring them food. :)
This batch of angels is from Lindsay Buckingfish, a 10-inch-tall black marble and his petite lover Stevie Fishnick, an 8-inch platinum. The result is 7 black marble angels and 10 white marble.