Good question. Lots of tanks, lots of aiptasia! Select feeding, I think is a key element in growing them. There's more than 100. The 100 that are not allocated to homes are the ones for this group buy. We started 2 years ago with 30gl of water now were at 500gl adding 55 more gallons today! We keep berghia in tanks with rock, some breeders use cups beakers or small vessels without water movement.
Never tried those methods so I wouldn't recommend them. Occasionally we do have a crash so we divide them. Management nightmare