Yes and no. Answers to that question depend on several factors. However, for one example of why you should not allow a breeding pair of cichlids to have multiple broods in the same tank, look no further than Julidochromis dickfeldi. Many species of cichlids can get along just fine with multiple generations of their own offspring, especially shell dwelling species. However, some adults cichlid pairs consider an older brood a threat to the newest brood and will treat the older brood(s) accordingly.
What else might factor into the older fry intolerance? Another species in the same tank.
My 33g long contains a breeding pair of dickfeldi. It also contains some ‘Lamprologus’ ocellatus…or it did. Now there is only a single male. And he may not be there much longer. At one point, I had five occies in that tank. I lost two to outright aggression.
I had previously successfully kept Julidochromis transcriptus with occies in a 40g breeder. I got spawns out of both species, concurrently. A 40 breeder is a three foot tank. A 33 long is a four foot tank. An example of why not all species behave the same.
Though I had the dickfeldi on one end of the 33 long and the occies on the other, the separation was insufficient. I’ve posted before about the dickfeldi fry leaking out from their rocks on the left end of this tank. Momma dickfeldi was very intolerant of the occies then, even though they were easily more than a couple of feet away. Why? Because her fry were on the move. As they moved right toward the occies, momma followed. The occies had nowhere to go but in their shells.
Last night when I went to feed, I noticed the momma dickfeldi harassing the lone occie all the way at the other end of the tank. That struck me as odd because her first brood, which had wandered considerably, were now several weeks old and were constantly hugging the rocks. I quickly figured out what it meant though – another brood. Sure enough, some little tiny wrigglers were around the rocks near the sand substrate. The previous generation of dickfeldi fry? They were sequestered into a corner near the rocks by papa dickfeldi. He was was protecting the current brood from his previous offspring while momma dickfeldi was keeping the occie in check. See the photo above. Really fascinating stuff if you’re a cichlid lover.