Hydnopora question
 

Ok,I broke my 75g in half when I was moving so I want to permanentlly move my hydno to my 10g nano. Question is on average how long are its sweeper tentacles having never seen them myself,I was warned when I bought it but I never had an issue in my 75.
Thanks in advance

Anything within 2"-3" would be at risk. My observation is that other coral grows much closer than that, but when the attack comes everything within 2"-3" will be killed.

Thank you,I'll go 5'' to be safe. I just had these visions in my head of 12'' sweepers wiping out my whole tank lol

Whoa! 2"-3"? I better move mine then I think.

How often do they extend the sweeper tentacles then? I have had mine for a while, its about 6"x4" and quite close to a bunch of gorgonians. The polyps or tentacles are always out but never more than like 1/2" or so. I guess I better be careful!

Ive had mine about a month and have never seen them extend past 1/2 inch either. But alot of people including the lfs say its a bad stinger with long tentacles,better safe than stooopid I allways say

Oh I totally agree. I knew they were very bad stingers, I just did not know they had long sweepers. Mine just always looks really fuzzy, like it has thousands of polyps and then once in a while they get what I thought was really long at about 1/2"...I can't imagine 2-3". That would look so cool though.

I have a fairly large Hydno and the sweepers are probably about 1.5 to 2 inches long. They almost always are out at night but once in a while they are out during the day. Helluva a sting; stung the crap out of a digi that I had too close.

Do they come out every night?

I wonder if mine is just not happy.

Mine don't seem to come out every night; in fact, they don't come out that often; unless it is very late and I'm not seeing them.

Mine swells like a balloon at night,the only time I've noticed sweepers is when it was agrivated. Maybe its a defense mechinisim,just guessing here.
It sure is purdy though lol

In my experience they usually only extend when there is something nearby it wants to eat. I had an acro beside one for months (about 2-3") and then out of nowhere one day it looked like a big spider web was covering it that was coming from the hydnophora. That acro was toast.

Good to know. I moved mine a bit farther away from the gorgonians.

FWIW, I had blue mushrooms once that killed my hydno, so some things can get closer. Just not other SPS :)

I think mushrooms can kill anything really. Mushrooms, Green Star Polyps and Xenia seem to be indestructible and grow right over other corals.

Only if mine touched something did you ever see sweepers(1 1/2"+). And man could they ever cause damage.

hydno
 

my 8 inch square fluorescent hydno never hurt anything as nearest thing is 1 inch away from it. i find that if other corals ie: monti, poci, most acros. birdsnest etc that dont send out sweepers can live almost within touching distance of hydnos.