Hammer Coral

[kiwis]

I'm not sure what the correct term is, but i'll call them tentacles.

Is it good or bad that I have several tentacles 2-3cm longer than others most days... typically earlier in the day once the light has come on and settles down later in the day.

Why do they do this? is it good or bad? should I do anything?

 

[RyanSweet]

That’s pretty normal in my experience. They extend “feeder” tentacles sometimes when the lights are low or off

 

[ScottR]

Actually the longer ones are called sweeper tentacles. They sting nearby corals so they can dominate a space. Some get extremely long and can sting other corals a foot away. You’ll see them dance around above the coral and sweeping to the sides. This is why it’s advised to keep a certain amount of space between corals. Feeder tentacles are much smaller and pull food into the mouth of the polyp.

 

[ScottR]

This is a pic of a lobo coral. The sweeper tentacles are circled in red, feeding tentacles in green. (Not my pic. From link at bottom). This coral is just being vicious here.

https://reefbuilders.com/2017/10/09/some-corals-can-be-total-bullies/

 

[DSC reef]

Sweeper tentacles are different from mesenterial filaments. Sweepers can sting from euphyllia but mesenterial filaments will actually digest a nearby coral. What's circled in red are mesenterial filaments

 

[DSC reef]

I'm not sure what the correct term is, but i'll call them tentacles.

Is it good or bad that I have several tentacles 2-3cm longer than others most days... typically earlier in the day once the light has come on and settles down later in the day.

Why do they do this? is it good or bad? should I do anything?

It's perfectly normal behavior for euphyllia

 

[kiwis]

do you feed these corals? if so what?

 

[DSC reef]

They would typically eat remnants of what was fed to the tank. Reef nutrition mysis, roe, brine. LRS reef frenzy as well.

 

[ScottR]

I use LRS reef frenzy. I use a turkey baster to feed. The fish eat the bigger chunks and some of the smaller pieces circulate around my water. I have a frogspawn which is in the same family as hammers. It retracts it’s long tentacles a bit so I know it’s feeding.