From past experience cichlids can breed earlier than most would think. A friend of mine had texas blues pair off and lay fertile clutches at 2 inches in length. The babies were fine and quickly outgrew their parents. Certain triggers, lack of water changes, temp changes, food changes, can trigger spawning at very young sizes. Another friend of mine breed FH's like crazy. The best breeders he has are under 6 inches. Most start to breed around 4 inches. When they get too big the male just ends up killing the female off. I guess he just gets too mean to breed.