I have a dal. sail fin molly that I breed with a solid black lyre tail molly...The fry grows to look like one of the parents... I have 2 out of about 100 that r a mix between them both ie...dal. lyre tail
You can get a mix of colors. Just because you got to black adults does not mean all black fry some times. Cuase one of there parents could have been white or black or even orange. But with 2 black ones your more likely to get more black ones.
Thanx for the replys guys, Since i put the female dal in the tank the other mollys havent bothered with her i have 2 other mollys (black) and they are both male and they chase each other round the tank trying to "bite" the other males "bits" i think they are batting for the other team