I also got a sun coral on my last purchase and it still hasn't opened. I know they only open after the lights go out, but this one hasn't opened yet. How long have any of you had one no open? I've been squirting zoomax and mysis at night but no luck so far.
Try taking them out of the tank in a bowl with some water in it and try feeding em that way.. When i had mine they were closed for about 3 days then I started feeding at the same time every day and in less that a month they were comming out during the day on their own..
Also, make sure it's not close to a soft coral (a leather, in particular). They can prevent the sun coral from opening. They can go for a couple of weeks without opening.
