Asterina stars eating zoas

[Cozmo4]

I noticed one of my zoa colonies looking poor over the last couple of days. Some of the polyps have been closed up and a couple of the polyps have been dangling by a small piece of flesh, like something has eaten through most of the base. This morning I see an asterina in the colony in the area where I've seen damage. I have seen a total of two of these stars withn the past month, even at night with a flashlight, so I don't think I've got many at all.

First, is it common for these to eat zoas? Next, how can I get rid of them? Thanks!

 

[geoxman]

yes it is common and you can FW dip or pick and pull. good luck

 

[Scott-CapeCoral]

Not all asterina stars eat them, if any at all. Most people say they don't. One thing I believe to be true is that will eat tissue that is already dead. So you may be blaming the wrong guy. Remove the starfish anyways because they breed horrifically and become an eyesore. Tweezers work wonders.

Oh and one thing you need to think about, is how much do you think one of those little starfish can eat? If you only see two of them- yet alot of damage, rethink, and keep searching for a differant culpret

 

[Cozmo4]

Got it. Thanks!

 

[MightyMoe]

Are the zoas glued to the rock? Sometimes hermit crabs will eat the glue.

 

[Scopus Tang]

I've personally never seen one of these actually eat zoas, nor have most of those with experience. What does happen, as was stated, is they will come in and work on cleaning up dead tissue or algae off of algae covered or dying zoas. I think that many of the "noted cases" are actually inexperienced aquarists who's zoas were already going, and they don't realize that the stars are just cleaning up what was already dying.

I've have had them sit on top of zoa polyps for a part of a day, and wondered if they were in fact eating it, but after they moved on the polyps were fine.

That said, I have seen a few posts from some individuals I trust saying that it has happened to them, so I wouldn't rule out the possibility.

There are many different varieties of the asteria star, so some may indeed be predacious on zoas.

 

[mstng67]

Asterina stars decimated my zoas several years ago, but I was negligent in properly dipping and quarantining a colony before adding it to my DT.

 

[joshnola]

I have personally experienced this. I began losing healthy colonies of zoas. I realized that my asterina population was out of control. I decided to find out what was going on.

I watched one night as 2 of those tiny asterinas, which you would think cant eat all that much, destroyed about 10 polyps of a zoa colony (one that was perfectly healthy and opened up during the day.) They did it in about 3 or 4 hours.

If the people who posted earlier do some searching on the internet they will find that there is no doubt that some species of asterinas do eat healthy zoanthids. Some species of asterinas are harmless and a great part of a clean up crew; it's just nearly impossible to tell them apart, unless one is very familiar with IDing them.

My solution was a harlequin shrimp, which wiped out my population of asterinas and paved the way for all of my colonies that remained to begin recovering.

 

[mstng67]

My solution was a harlequin shrimp, which wiped out my population of asterinas and paved the way for all of my colonies that remained to begin recovering.

This was my solution also. However, you need to be aware of the harlequin shrimps special dietary needs (Stars).

 

[joshnola]

This was my solution also. However, you need to be aware of the harlequin shrimps special dietary needs (Stars).

Yes, thank you. I forgot to mention that. To the original poster, if you do get a harlequin you will need to provide starfish for it to eat every 2 to 3 weeks. I feed mine a chocolate chip star every 2 weeks. It's very neat to watch!

 

[Scott-CapeCoral]

I have personally experienced this. I began losing healthy colonies of zoas. I realized that my asterina population was out of control. I decided to find out what was going on.

I watched one night as 2 of those tiny asterinas, which you would think cant eat all that much, destroyed about 10 polyps of a zoa colony (one that was perfectly healthy and opened up during the day.) They did it in about 3 or 4 hours.

If the people who posted earlier do some searching on the internet they will find that there is no doubt that some species of asterinas do eat healthy zoanthids. Some species of asterinas are harmless and a great part of a clean up crew; it's just nearly impossible to tell them apart, unless one is very familiar with IDing them.

My solution was a harlequin shrimp, which wiped out my population of asterinas and paved the way for all of my colonies that remained to begin recovering.

I dont believe you in the slightest bit. Two of those stars cannot eat 10 zoas in 3-4 hours. You wouldn't have sat there aswell after watching them eat even one of them. Stop lieing and tell this man that you may have saw them 'picking' at your zoas that were already dieing.

 

[Johnny C]

I dont believe you in the slightest bit. Two of those stars cannot eat 10 zoas in 3-4 hours. You wouldn't have sat there aswell after watching them eat even one of them. Stop lieing and tell this man that you may have saw them 'picking' at your zoas that were already dieing.

Calm down with the harsh accusations. They definatly can and possibly will eat zoanthids; there are hundreds of different sub-species and all are <i>not</i> all created equal. I had a perfectly healthy frag of purple hornets, and after my starfish were through I had 3/6 polyps. I then bought a Harlequin Shrimp and haven't lost a single zoo polyp since. (BTW, the Harlequin is now re-homed where he can he happy and well-fed).

 

[Scott-CapeCoral]

Calm down with the harsh accusations. They definatly can and possibly will eat zoanthids; there are hundreds of different sub-species and all are <i>not</i> all created equal. I had a perfectly healthy frag of purple hornets, and after my starfish were through I had 3/6 polyps. I then bought a Harlequin Shrimp and haven't lost a single zoo polyp since. (BTW, the Harlequin is now re-homed where he can he happy and well-fed).

No, I won't lol. He did not sit at his tank for 4 hours watching 2 starfish, the size of pencil erasers, eat 10 zoo polyps.

1. They cannot eat that much. It's impossible. Can you eat a bus in one sitting?

2. Nobody in thier right mind would sit there for 4 hours allowing this.

3. They cannot eat that much... Can you eat a bus in one sitting?

lastly.

4. Nobody in thier right mind would sit there for 4 hours allowing this.

 

[Cozmo4]

All right, guys... I didn't expect to set off such a debate. For clarity, the zoa colony was perfectly healthy and growing very well. I can assure you that the stars were not eating dying polyps. The one I've seen on them appears to be eating through the base so that the polyp falls off the colony - only a couple of polyps.

Scott-CapeCoral, Nobody in their right mind would sit there for 4 hours allowing this....unless the tank is 30" deep on a 36" stand with a 10" canopy and the asterina is on the underside of a zoa colony growing on a tonga branch in the rock work near the sand bed. I simply can't reach to pull them off. I'll lose a few zoas before I'll tear apart my rock work and risk damaging a lot of other stuff in the tank. So, I suppose I'm not in my "right mind", huh.

Oh, and many animals can eat a heck of a lot more than we can relative to their body weight. It all depends on metabolism. Not sure it would be accurate to compare a human eating a bus to a starfish eating a couple of or parts of a couple of zoa polyps.

 

[Guygettnby]

when i had this problem it was not asterina stars that caused the problem. usualy when zoanthids start to fall away and there matt starts to melt away or disaper the problem is caused by spiders.

there are asterina stars that eat corals out there but there are so many species and sub species out there that it is almost imposible to know if you have zoanthid eating asterina stars.

the only real thing you can do here is to dip your zoanthids in a quality coral dip like revive or lugols. i highly am against fresh water dipping of zoanthids. expecially when they are already injured or in bad shape.

 

[tuckdawaytoo]

My asteria starfish were eating coraline like crazy...took several nights with tweezers and a cup to thin them out...have been getting along nicely since.

 

[corigan]

I've been pulling astrenas off my zoa's nightly for about 3 weeks now. My zoa colonies have never looked better. They open up daily now, lol.

 

[20pilot]

Removing

Removing

How do you go about removing these guys, just reach in with your hand and grab them or shoulld i be using another method. Recently it seems that these are coming out in numbers in my tank. Is there anything I can so to stop this?

 

[Scott-CapeCoral]

Tweezers, harlequin shrimp, or both.

 

[Scopus Tang]

All right, guys... I didn't expect to set off such a debate. For clarity, the zoa colony was perfectly healthy and growing very well. I can assure you that the stars were not eating dying polyps. The one I've seen on them appears to be eating through the base so that the polyp falls off the colony - only a couple of polyps.

Interesting, I'd be curious to know if the star was actually eating the matt of the polyps or consuming something that the matt/polyp was attached to, thereby casting the polyps adrift. Again, I don't doubt that there are asteria out there that eat zoas, but I do firmly believe that most "sited" cases of this are a mistake. I do know that a researcher on another forum has been advertising an interest in coral-eating asteria, and has yet to actually get one that eats healthy corals. Again, not saying that they don't exist, just saying that I don't think they are encountered as often as is thought.

My asteria starfish were eating coraline like crazy...took several nights with tweezers and a cup to thin them out...have been getting along nicely since.

This type of asteria seems to be much more common. Somewhere I read that many corals will attach over a base of coralline, if you have stars that are eating the coralline from beneath the polyps is it possible the polyps would be cast adrift? Just curious