Jaybird
Aquarium Advice FINatic
I got an open brain from a fellow reefer and it was about 1/3 of the size in his tank. I've moved it into an area that's more open but it just keeps on expanding. The thing is probably 6 to 7 inches across when lights are on. It's got three mouths, but if it keeps expanding I won't have anywhere else to keep it without it pushing against the live rock.