All those pics look sick!
My seabae is about 16" across when open.
I've had 'him' for over a year.. I give it 2 krill every 2 weeks or so and the rest of the time I just let it catch what ever the fish miss.
He is huge! They aren't picky eaters when they are happy.
My fish get mysis, and Reef Nutrition oyster feast, phytofeast & arctipods.