I am wondering if this coral might be damaging a couple small sps I have near it that are looking pale with no polyps out lately. Tissue looks OK but no polyps any more.
It was given to me and I was told the name but have forgotten it.
Could it be stressing the ones near it? I am at a loss whey they have not shown any polyps and all my others not close to it are bushy all day long.

Yes I would bet that is exactly your issue, those are nasty corals, very aggressive. Hydnophora

Thanks. I plan on giving it away (just have to think of someone I don't like and give it to them, lol-kidding) even if it is not what the problem is, but I bet you are right.
As I said before, all the other sps that are not down current of it are acting as they always have.
Yes, that is the name I was told. I couldn't remember. I need to start researching prior to acquiring it seems.


Wow. Just did some reading on them.
No doubt it is the problem.
It is out of here asap.

FWIW I have a 5" wide/tall hydnophora colony in a 25g that doesn't bother anyone except the stupid zoanthids that are trying to grow around the base (they always look hunched up).

Are you running clean, fresh activated carbon? I definitely run carbon partly b/c of this.


Here's a pic of the one I have, looks identical to the variety you have. Actinic shot. It really is that green.

No, I have not been running any carbon. Thanks for the info, looks the same. My tank is really small and the real estate it is occupying could go to better use anyway. It was a freebie so I am not going to chance it.
That looks spectacular BTW.

I have one of those and I really like it but maybe I am wierd lol. And something very odd, I wonder if any others have this happen but when I orginally placed it it was small and about 3 inches away I placed a purple/brown polyp monti digi. Well they have both grown alot since placement and originally when they got about 1/2 close the hydno reached stuff over onto the digi that was in reach and ate it away to the bone.
Now a couple months later, the digi recovered and they are like a cm away and nothing is happening at all. Odd?

They are kind of like acan enchinatas, sometimes they will attack, sometimes they don't. Don't place them by anything you value highly.

Hydnophora can kill aiptasia, so that gives you an idea of the damage it can do. I really like this coral and it can really take off in the right environment.

So true, plus their likelihood to attack rises exponentially depending on how expensive the pieces next to them are...