strange 6 and 7 armed Starfish breeding like crazy

[thesaleens7r]

i have a weird starfish in my tank that came in on some liverock. they have some 6 and some 7 arms on them usually 3 of the arms right next to each other are shorter in size. they are starting to breed like crazy. today i came home and one was on the glass of my tank. i looked closer at it and it looked as if it had split in half???? i took my magnet float cleaner and knocked it off and sure enough it was 2 pieces?

[tsintse]

Asterina's

[Scott Riemer]

Asterina's

+1

[thesaleens7r]

good? bad for my tank?

[GrandeGixxer]

Some are bad for some SPS. Get a trigger.

[Scott Riemer]

good? bad for my tank?

Mine have never caused any problems. Keep an eye on the population though.

Get a trigger.

Hope the smiley indicates you are joking.

[Christopher Marks]

http://www.nano-reef.com/invertebrates/?id=9

[joesmoe517]

brown asterinas have been known to eat sps and zoanthids. ive also heard of people saying they eat coralline algae (which i dont understand but multiple people have told me of this happening at work). I would pick them out whenever you see them. This is what we do in our tanks and just let them dry out on top of the light and once youve got 30 or so you can string them together for a nice necklace

[SPS20]

I have them in my tank. They are definitely Asterinas. There are species of Asterina that will eat SPS, but they are relatively rare. I have had them in every tank I have ever had, and I consider them to be harmless scavengers. This is not to say that yours won't eat SPS, but rather that there are species that look just like that that don't eat SPS.

 

Now, they can and will eat some coralline algae, so that part I can attest to. If you have reason to suspect that they are doing harm, and have no starfish in your aquarium that you care about, add a harlequin shrimp or 2. They eat exclusively starfish, and will demolish the population of Asterinas in your aquarium in short order. Regardless, I suspect that if you have alot of them and your SPS are still ok, thats pretty good evidence that they aren't the type that eats corals. They do also eat hair algae, diatoms, and detritus (if they are the same kind I have) so I consider them part of my clean-up crew.

 

- Josh

 

note: DO watch them carefully for awhile to be sure they don't eat SPS, but I am under the impression that most varieties will not eat SPS. There are reports of Asterina's eating SPS, but alot more reports of them being harmless. Don't even bother trying to ID your starfish down to the species level, all the Asterina species look almost identical to each other to the naked eye.

[The Propagator]

brown asterinas have been known to eat sps and zoanthids. ive also heard of people saying they eat coralline algae (which i dont understand but multiple people have told me of this happening at work). I would pick them out whenever you see them. This is what we do in our tanks and just let them dry out on top of the light and once youve got 30 or so you can string them together for a nice necklace

 

 

No brown asterinas with two extremely longer legs like vampire teeth have been known to eat SPS not just brown asterinas

That will send a shock wave of fear into every ones heart.

 

The 7 legged guys you have are just the 6 legged version getting ready to split.

They are harmless and GREAT algae eaters. They get in to all those nooks and crannies, as well as around the base of the coral. Which is where you will find them A LOT ( as well as on the rock work) check the glass at night and you'll see a bunch too.

Absolutely good guys. Leave'em in. When you get enough of them sell a 10 pack on Ebay or something with some macro algae for $10.15 bucks. People love them.

[John30507]

Hmm.. My science teacher offered me some of these. Should I take them?

[SPS20]

Hmm.. My science teacher offered me some of these. Should I take them?

Do you have a sump? If you do, take a few and toss them in there. Why turn down free scavengers?

[John30507]

Do you have a sump? If you do, take a few and toss them in there. Why turn down free scavengers?

 

Bio Cube sump. No modifications. Which chamber should I put them in? Could I put them in the Main tank? Any precautions with other tankmates (Gold Stripped Maroon Clown, Scooter Blenny, Hermits, Snails).

[SPS20]

Bio Cube sump. No modifications. Which chamber should I put them in? Could I put them in the Main tank? Any precautions with other tankmates (Gold Stripped Maroon Clown, Scooter Blenny, Hermits, Snails).

 

Well, there is pretty much zero chance the starfish will hurt fish, snail, or hermit crabs. Do you have any corals?

 

- Josh

[The Propagator]

If they look identical to the ones pictured they will not harm your corals.

I have thousands of $$ of live stock in several tanks full of them.

Its the one with Two Extremely loner legs you have to worry about.

[c est ma]

+1

 

More input:

 

http://www.garf.org/STAR/starfish.html

 

--Diane

 

PS: Echinoderms are so cool. Why not give it a chance?

[John30507]

Oh no! I've introduced a pest! I'm glad that I don't currently have any corals. I will try to find this starfish before it is too late.

 

EDIT: I forgot to add that it has three legs. One long leg, and two smaller ones. This is the coral eating starfish, right?

[c est ma]

Well, not necessarily. IME most Asterina have uneven legs because they lose them to asexual reproduction. (Here's a pic of one that I recently got as a hitcher: )

 

 

Take a good look at the pics in the GARF link I posted a few posts ago and see what the ones with exceptionally long legs look like...

 

--Diane

[The Propagator]

 

Thats an SPS eater and the only sps eater of the bunch I know of or have ever came across.

GARF has a big write up on them but they also include the smaller even legged asterinas which is incorrect.

if you see an asterina with equal legs ( or one that has split ) "eating" at a coral it's not actually eating the coral. It's eating the decaying tissue off of the skeleton after it has died.

where as the vampire asterinas will eat healthy coral.

[c est ma]

 

GARF has a big write up on them but they also include the smaller even legged asterinas which is incorrect.

if you see an asterina with equal legs ( or one that has split ) "eating" at a coral it's not actually eating the coral. It's eating the decaying tissue off of the skeleton after it has died.

where as the vampire asterinas will eat healthy coral.

 

Thanks, Props, that's very good to know. Whenever I post that link again I'll be sure to add that caveat.

 

Yet another case of something that's being helpful by cleaning up the already dead (bristle worms, certain hermits, etc.) being accused of the murder!

 

--Diane

[The Propagator]

Yup. Its sad they get such a bad wrap.

[SPS20]

Yup. Its sad they get such a bad wrap.

 

Well, garf has for years insisted that Asterinas are all harmful despite massive evidence to the contrary. I don't know why they insist on sticking to that position, but they do. There is some good information on that site, but that particular tidbit is best taken with a grain of salt. I blame garf for the bad rap they have, as it is an oft-cited source when the subject comes up. Garf also advocates some really odd ideas about lighting and filtration, but thats an issue for another thread. Garf does have one of the most amazing captive repositories of genetic diversity of cryptic benthic fauna in the world. (they have old refugia and sand beds running in their systems that have absolutely obscene amounts and diversity of life growing in them. This is a huge contributor to the success of their systems, IMO.)

 

I will once again repeat, I have had alot of Asterinas in in every tank I have ever had, and I have never had problems with them. Thus, there MUST be at least one species that is reef-safe. My 120 gallon system (sadly no longer mine) at its peak must have had tens of thousands of them in it. They were EVERYWHERE, and my corals were totally fine.

 

Also, about the uneven arm length thing: keep in mind these things reproduce by division, so will very often have arms of differing lengths and varying numbers of arms. I have never personally encountered the "bad" ones, but as The Propagator said, look for the really long arms, not just uneven arm length.

[The Propagator]

Really long TAPERED to a sharp point arms

[c est ma]

Well, garf has for years insisted that Asterinas are all harmful despite massive evidence to the contrary. I don't know why they insist on sticking to that position, but they do. There is some good information on that site, but that particular tidbit is best taken with a grain of salt. I blame garf for the bad rap they have, as it is an oft-cited source when the subject comes up. Garf also advocates some really odd ideas about lighting and filtration, but thats an issue for another thread. Garf does have one of the most amazing captive repositories of genetic diversity of cryptic benthic fauna in the world. (they have old refugia and sand beds running in their systems that have absolutely obscene amounts and diversity of life growing in them. This is a huge contributor to the success of their systems, IMO.)

 

I will once again repeat, I have had alot of Asterinas in in every tank I have ever had, and I have never had problems with them. Thus, there MUST be at least one species that is reef-safe. My 120 gallon system (sadly no longer mine) at its peak must have had tens of thousands of them in it. They were EVERYWHERE, and my corals were totally fine.

 

Also, about the uneven arm length thing: keep in mind these things reproduce by division, so will very often have arms of differing lengths and varying numbers of arms. I have never personally encountered the "bad" ones, but as The Propagator said, look for the really long arms, not just uneven arm length.

 

Interesting, Josh! I saved that Garf-Asterina link long ago for its pics and possibly its "experimental data," but I'm embarrassed to say I never investigated Garf further...even though I had "good intentions" to do so, of course...we all know where good intentions pave the path to...

 

When I post it, as you may have noted, I do take care to also add that a great many reefers have had NO problems with Asterina coralophagy (is that a word? ). From now on, I'll just call attention to the pics with the "Really long TAPERED to a sharp point arms" as Props put it. When you look at those, it becomes pretty easy to distinguish them from the usual "amputees" we see...

 

--Diane

[H7brandi]

The GARF article mentions how to identify the vampire asterinas damage on SPS, but what kind of damage would you look for in zoanthids? Do colonies just start to diminish in quantity or polyps, do the polyps have obvious "gnaw" marks, etc?