Sweeper tentacles

[CSeaSee]

I've got a Euphyllia ancora which was purchased from my LFS. The coral is aquacultured; it's never been in the wild. I always hear about sweeper tentacles on LPS and have certainly seen pics of them, but I've never witnessed them on the one rather large head that I have. Regardless of how long the lights have been on or off, there are never any present. I've had this head for about 7 months now, and it's doing phenomenally. During the seven months, it has budded 6-7 times, and several of the baby colonies are beginning to look quite nice. I've never been able to get the coral to eat directly, though, regardless of the food. I think I may try some cyclop-eeze this weekend, but I had four questions:
-Why are there no swepper tentacles? Is this b/c it was aquacultured?
-Why won't it eat? Should I worry?

[zhenya]

Carl,

It would be hard to say why it is not accepting any of the foods you offered. When I kept one for a couple of years it ate like a pig, mostly mysid and other, meaty foods.
As far as sweepers on this particular coral, is there any other corals that are close to it in your tank? And is it recieving lots of current? I know that mine did produce some long sweepers if I would put something remotely close to it or if it recieved strong currents for a while. Eric Borneman talks about it in his Aquarium Corals book and states that exeptionally strong currents propmote sweepers formation.

[CSeaSee]

Gene,
The only other corals that are close to it are a couple species of corallimorpharians. They are about 4-6 inches away when everything is fully expanded. The hammer is my only stony coral in the tank. It receives moderate-strong indirect current. Because of its size, I don't risk giving it too much... a couple of time a powerhead will redirect itself directly at the coral and the polyps retract.
I'm assuming that because it's reproducing at a pretty good clip that I'm doing something right... this is my first stony coral, so I'm trying to see if it's going well.

[zhenya]

Gene,
The only other corals that are close to it are a couple species of corallimorpharians. They are about 4-6 inches away when everything is fully expanded. The hammer is my only stony coral in the tank. It receives moderate-strong indirect current. Because of its size, I don't risk giving it too much... a couple of time a powerhead will redirect itself directly at the coral and the polyps retract.
I'm assuming that because it's reproducing at a pretty good clip that I'm doing something right... this is my first stony coral, so I'm trying to see if it's going well.

Well, if it is growing at the good rate I wouldn't worry about anything else at this point.
I believe E.Borneman mentioned in his book that this coral are sensitive to some soft coral toxins, specifically some of the Sinularia species. Few mushrooms nearby probably wouldn't affect how your coral does. As long as there is no direct contact... You are definately doing something right if you can see coral growing... ;)

[CSeaSee]

Well all righty then! Hopefully when I get a decent camera I'll snap some pics to show everyone. Thanks!

[Ninong]

-Why are there no swepper tentacles?

Probably because there is no need for them. Sweeper tentacles are just regular tentacles that are modified for warfare. They develop in response to a perceived threat.

Is this b/c it was aquacultured?

No.

[BubbaWPB]

None of my E. ancora or E. divisa corals have developed sweepers. They are in their own corner of the tank, not near other corals. My E. glabrescens, on the other hand is constantly sending out "sweepers" despite trying to place it as far away from other coral as possible. The sweepers are not a visibly different type of tentacle, such as Galaxia or favia produce... the sweepers on Euphyllia look just like the other tentacles, only they are suddenly much longer. The E. glabrescens (torch corals) are known to be more aggressive than the other Euphyllia species. One or two long sweeper tentacles can be easily shortened with a pair of scissors if it is stinging something not-so-nearby.

My frogspawn and anchor corals spit out most of what I try to target feed them. No big deal. They are healthy and growing, so I don't worry to much.

[CSeaSee]

Thanks everyone for the input!

[kevinpo]

Hello Carl,
Sweeper tentacles are used for defense of the coral's space on the reef. They can use them when they detect another coral. This can be through physical contact or chemical clues. Corals can learn over time who is in the tank with them and get used to their neighbors and either quit extending sweepers or never have them to begin with. Corals that have lived in captivity with other commonly kept corals have a tendency not to produce sweeper tentacles for that reason.
I have seen a coral produce sweepers after not having any for more than 5 years when a new coral was introduced into the tank (3+ feet away in a 550 gal tank ).

LPS corals do not have to be fed directly if the lighting is intense enough and/or you are feeding your fish.

Regards,
Kevin

[CSeaSee]

LPS corals do have to be fed directly if the lighting is intense enough and/or you are feeding your fish.

Hi Kevin,
Thanks for the input... that's a really cool story! Always interesting to see how different life can be. For clarification, is the above quote accurate?

[zhenya]

I think Kevin missed word "not" in "do not" but I could be wrong.

[kevinpo]

Oops Gene is right See what happens when you are up at 2AM playing on the internet

Regards,
Kevin

[BubbaWPB]

Well, I put the torch coral from hell into the new tank thinking that I could isolate it. There isn't anything other than sand and rock in a several foot radius. Apparently strong current DOES promote sweepers, just like Gene said in posting #2 above...

[dreams]

"sweeper tentacles"...is that what extends from my button polyp at night?...looks like it is feeling around for something

[BubbaWPB]

Button polyp? I don't think they have sweeper tentacles... it may be a worm or a snail that is sending out some sort of sweeper... unless button polyps really do have sweepers....

[dreams]

i know it's not a snail.......could be a worm......it is about the thickness of fishing wire, 1 1/2 inches long (the part i can see, anyways)

it was weird, cause it looked like it was pulling on the rock, get really rigid

[Reefland]

I guess it depends on what a button polyp is. There are some LPS corals with the common name of Button Polyp that could very well exhibit the use of their sweepers.