I understand that there are records (mostly by non carthagenians) regarding their love of child sacrifices. But to what degree was this phenomenon prevalent. I would also like to learn wether it involved fire as it is mentioned that in the siege of carthage some women threw their children into the fire following them themselves.
I answered a very similar question last year that might answer your questions as well.
I do have to add one correction: Herodotus does in fact reference the Phoenicians making a human sacrifice, but the context is very different and may just be a reference to the phenomenon in general. As I say in that answer, the accusation still was not made of the homeland Phoenicians very often, and there isn't evidence in the major Phoenician sites (so far as they have been excavated).
Herodotus also seems to have been generally unaware of the Judeans and other people of the southern Levant, and may have lumped them together with Phoenicia at times.