The tissue still appears to be intact, so it may well still have a chance. Keep the light on the low to medium side. Gentle undulating currents from both sides is ideal. Strong flow from one direction is undesirable. I can remember one of mine took quite a while for the tentacles to pop out & even longer to fully extend. When happy, they will grow fairly quickly, to you will probably need to supplement & maintain Ca/Alk/Mg levels. If your levels are sub par, I'd begin correcting that right away. With my initial frags, I glued them to a flat rock as sand on the tissue isn't a good thing imo.
While some gonis are indeed difficult to keep long term, others are very hardy. It seems the green varieties are the ones that have earned the reputation as nearly impossible to keep alive long term (I've lost one).
They are great corals, often a show piece in a reef. You have great color and movement all in one package. There are other examples of successful Goni keepers on RC.
In the US, an aquaculture facility called ORA in Florida has sold their captive bred "Red" variety for a long time & they're a proven winner. I've had two and both were some of the most hardy stony corals I've ever kept. I'm not sure if other red colored specimens that come from other sources are the same species/morphs & will prove to be as equally hardy however. A local LFS has a display tank with a non-ORA beauty, red with gold speckles, that's been alive & growing for several years. So while I'm sure ORA can't ship to Australia, you might have some luck with yours. It's not over til it over. Best of luck!
