Galaxea Coral Sweeper Tentacles - How Far Can They Reach?

Miss Piggy

New member
Hi got me a nice small(ish) galaxea coral (green). Atm its approximately 4 inches from my zoas, 5 inches from my mushrooms, and 6 inches from my leather. All approximate lengths, eyeballed with no ruler at hand.

Also sorta offtopic but any chance i could get range for a hammer coral? 6 inches sound about right? That's what i was told.

Thanks for your time


New member
I don't have a galaxea coral so I can't help you there. I do have several hammers though. My larger hammer is a wall hammer and it has a skeleton that is about 6 inches across. It never seems to extend its tentacles. It has grown alongside several different types of zoas and a toadstool without any problems.
I also have a branching hammer that is about baseball sized. It does extend its tentacles from time to time about 2 inches beyond its normal size.


New member
A long way!
I have had there sweepers 12" plus. Now I don't do galexia any more they take over a substantial area that is not safe for its neighbors.


New member
Mine is small and stretches out about 6-8 inches

And I do believe it damaged my mushroom cuz one of the corners looks a bit weird now


New member
i had galaxea which would have it sweepers almost 8 inches out. If you keep it in high flow then the sweepers won't be that long but still very potent sting. I got rid of mine becuase it grew too fast and i wasn't able to keep any corals around it.


New member
my green galaxy 4x2 sweep 6-8" out. nice to see the tentacle sweep when moon light is on..glow!!!!!!!!!!


New member
Can't help with your primary question, but we have a branching hammer and I have yet to see it extend any sweeper tentacles at any time of the day or night. Left some space around it just in case.


code monkey
You can expect 10-12" in the direction of wherever the flow is aiming, especially if it feels like there's a coral in that region. It's pretty strong, so chances are it's going to nuke those corals around it. As far as hammers they tend to stay shorter but it depends on flow, 4-6" is definitely possible.