There is not that large of a size difference in the severum species. Sometimes the rotkeils are smaller but I also saw a couple adult males at a cichlid dealer that were every bit of 10" and bigger than most efasciatus I'd ever kept. These were pond-raised so it's unusual for them to grow this large in tanks but it shows that it's possible. Rotkeils will still hit 7 - 8" which is only maybe an inch or so below average for efasciatus.
If by pink tilapia you mean Oreochromis mossambicus, that's an African cichlid with the potential to grow well over 12" long. They would not be suitable for anything less than a 6' tank, IMO, and may even outgrow that.
If by pink tilapia you mean Oreochromis mossambicus, that's an African cichlid with the potential to grow well over 12" long. They would not be suitable for anything less than a 6' tank, IMO, and may even outgrow that.
