losbeek

I think the Sun coral only opens in low/no light

yeah, ive read that the lighting conditions dont necesarrily dictate feeding responses. but i guess i will have to try that. i have been trying to feed them after the MH's go out.

also, when i checked them this morning they looked like they were "trying" to open. im thinking just keep trying otherwise they will definitely die.

I have a colony that is 100+ heads in my grow out tank. Mine opens up whenever I even feed my main tank it can just "smell" but at the beginning I had to use the tupperware method. Yours looks alot healthier than mine did a year ago. Put it in a tupperware with tank water and sprinkle a little frozen cyclopeeze in the water. Then put a towel over it (to make it dark) and wait 10-15 mins. If you see any tentacles poking out, place a frozen brine shrimp (I use hikari flatpack brine and hikari spirulina brine) on the tentacle. The key at the beginning is it give it a chance to eat without any flow, the coral uses a lot of energy to open its polyps so you need to make it worth their effort.

P.S. to my last comment...I try not to leave them in the container for more than 1 hour as the water then cools down and becomes gross. But what is nice about the container method is that you don't have to dump all of that uneaten food into your reef. My suncoral now eats 2 cubes of spirulina brine per day, I just toss it in my 40 breeder frag tank and let the powerheads blow it around for the coral to eat. That said I have ~225g of water volume, zeolites, biopellets and a kickbutt skimmer to deal with the extra nutrients.

Good luck and keep asking questions.

great advice, thanks
i didnt mention this but i did try the cut out half gallon milk container method to stop the flow to see if i could get them to eat but no dice. (im thinking midnight was right, cause i did have my actinincs on) as u can see the bottom polyps opened up but none of the larger top polyps

They really need to "smell" food especially right when you first acquire them to be willing to open up. Shipping/collection/sitting in the store unfed for days if not weeks really p*sses them off...try the container method and let me know how that goes.

Check on this coral 15 minutes after you've fed the tank, or 30 minutes after lights out. If it is open, feed it with the flow off. Try to give a piece of mini-mysis to each mouth, even those that are half-closed. 15 minutes later, check on them again and see if they opened up further.

I've been keeping suncorals for years now, and they have to be fed regularly to keep them happy. When I get lazy, the coral suffers. I have three colonies right now, two yellows and a deep dark green branching kind.