IT DOSENT MATTER!
she was asking about the agression and max. size, but KKP and BP are exactly the same fish! Bps just have the 'notch' and KKP's don't and don't have deformed mouths. But no matter what 'Kind' of parrots they are, they're ALL parrots. Just a line bred RD x RSSynspillum. So It dosen't matter. TO the person who started this thread: you can apply knowledge of care of BP's to KKP's and vice versa. They are just the same fish with different mutations/parents. But the same fish nonetheless