I was sure the Senegal was a fast grower, with mainly albino and inbred strains suffering from slow growth. I specifically waited with getting the Senegal so it wouldn't outgrow and eat the Del and Polli. I don't see the logic in this either, in hindsight. Remember that this was just days after obtaining my first Ropefish and learning about Polypterids.Mine have the small fins of a female. Don't think at all it's males.
As for captive breeding they may well have smaller broods at a younger age but the Senegal is known as a slightly slowet growing bichir in general too but mine are my fastest growing fish. The physical differences between my Wc and Cb sens are huge physically and in appetite hehe.