Can anyone help. What’s happening to my torch coral it was fine half an hour ago now all tentacles have receded and the tissue has blown up. There are no rips tears or browning in the tissue or head and it isn’t receding
Half an hour is kind of soon to be able to say what happened IMHO. It could be something as simple as a fish bumped into it, a clownfish started trying to host it for the first time, chemistry changes, etc.
Let's see how it looks tomorrow though. Hopefully it's perked back up by then, but if not we can look into it further. The first thing we'll be asking about is your water chemistry, so have it handy!