I love to see when sun corals opening up.
Their colors are so bright and rich, its just awesome to stare and admire them.
Most reefers have problems to see their sun opening up upon purchase...i might just have a solution for that.
1) Sun corals do not like bright lights, so place them in a relatively dark place
2) Make sure the get some water flow
3) If all else fails,
Hang a small piece of prawn meat about 1-2 inches above it for 5-10 minutes. You will notice that they will start to balloon and eventually there tentacles will start to appear. Once they open up fully, direct feed them with brine shrimp using a feeding tube. Repeat this process every 3 days. eventually your suns will get use to it
Please do not forget to remove the prawn meat after feeding.
Hope this helps.
I have a few sun corals for adoption making space for some other corals. Do pm me...