sun coral polyp extension

[ptownfro]

I have been wondering why my frags of sun corals open everyday all day,while the colonies only open at night or when food is added. Has anybody else noticed that a freshly cut frag seems to open up right away, if its not slimeing up. Please chime in to why they would open after fragging.

 

[noy]

Are you sure they are the same species? frags are usually of dendros which have larger polyp heads - since they are branching they are generally easier to frag. Colonies tend to be Tubastraea colonies.

If they are the same species - it just may be the flow orientation. I have micranthus (black sun corals) on different parts of the tank - some stay open during the course of the day and other only open at night.