Is this brown jelly disease on acan?

Is this what they call the BJD? If so, this is the first time happening in my tank and I have to take the sad coral off before it spreads.

There's some sort of dirt that covers few Acan holes (there's 2 in the middle as shown in the pic) ... to be honest, I'm not too sure if the color is brown but it doesn't look happy that's for sure.

Any update would be much appreciated!