Asterina star?

[ClownfishAnemone]

I'm wondering if this is an asterina star or not and if it is i'll remove it immediately

 

[wtdenk]

Looks like it to me. I had one come on the shell of a snail. I removed it as soon as I could. The risk is their proliferation.

 

[Double monti 61]

Remove it due to your ignorance and the misinformation you are spoon fed diversity in your system is more beneficial than you are led to believe i would submit a photo but my system is not the cookie cutter system most people want to have not the beautiful acropora super perfect tank and I am very happy with that but I do have growing coral and invertebrates!

 

[neilldrever]

Yes it's an Asterina but the fact it's on the glass suggests it's one of the 95% of Asterina species that eats film algae and is therefore free CUC. As with any animal their population size is controlled by the available food supply so if you see a tank overrun with these little guys is due to the abundance of algae, nothing else. Control the algae and you'll control the Asterina population. I personally quite like them and have never had an issue with them taking over or eating any soft coral polyps.

 

[tehmadreefer]

Get rid of it unless you like hundreds and all your corals munched.

 

[Cole.mormon]

If it gets prolific buy a harlequin shrimp, but beware, when they run out it will have to be fed starfish

 

[Double monti 61]

A lot of that around these days speak not if thou does understand the true meaning of life and my tank is only 15 gallons pic right now

 

[Hairyteeth]

If it gets prolific buy a harlequin shrimp, but beware, when they run out it will have to be fed starfish

Gets expensive unless you have a sump/arm factory lol

 

[Cole.mormon]

I have a sump lol

 

[Johnz]

Yeah, that looks like an asterina star to me. They have been in my tanks for over a decade and I think of them as part of my cuc. I have heard the stories of them over taking a tank, but I think that is not the norm. When my maintenance slips and i dont keep up with things they seem to increase in number, but never out of control. I will say that if you see one, odds are there are more deep in the rock, so remove it or not, they're prolly part of your tank already. Either way, you're probably OK.

 

[Hairyteeth]

I have a sump lol

I also have an arm factory that feeds my nano lol

 

[ISpeakForTheSeas]

Just to add some info on these stars to the discussion (pasted from another of my posts):

Yeah, asterina starfish (technically Aquilonastra, but known in the hobby as Asterina). Personally, I like them, but they do reproduce quickly (very quickly), and some people believe they eat corals (see my quotes below).

ISpeakForTheSeas said:
With regards to whether or not they eat corals, it might be a species specific thing, it might be a you have way too many starfish so they're out of other food options thing, or it might be they're eating the slime coat/mucus on the coral rather than the coral itself (see below).

The quote I referred to in my quote above:

Timfish said:
It's an Aquilonastra spp. starfish and is a great scavenger. I see them with anywhere from 4 to 12 legs. The whole discusion around them seems to me excellent examples of misidentification, mistaken behaviour and assumed causality based just on heresay without looking at the research. Asterina spp starfish are preditary but only reproduce sexually and are shortlived so while it's possible some might get into a tank even if it did happen it's not going to be around long. Aquilonastra are one of the uncommon species that reproduce fissiparous or by splitting so are easy to identify by the different sized legs regrown after splitting. They perform an important function not only feeding off algae films but also feeding off microbial films including those on corals (at least ones that don't sting). FYI the mucus coating on corals ages and corals have to periodicely shed it to renew it and maintian healthy microbial processes (Ref 1, Ref 2). If Aquilonastra are feeding on zoas or softies I'll argue they are either benign or even beneficial as they may be reducing the unhealthy older mucus which can be full of unhealthy microbes which the animal is trying to get rid of and are far more likely to be the actual problem.

Here's an example, this Toadstool is doing one of it's periodic sheddings. The Aquilonastra have been in this system for years but only climb onto the Toadstool when it's shedding. In the first picture you can see the old mucus film, Aquilonastra starfish and areas they have cleaned off. The second picture shows the Toadstool a week later.

 

[MaxTremors]

Yes it's an Asterina but the fact it's on the glass suggests it's one of the 95% of Asterina species that eats film algae and is therefore free CUC. As with any animal their population size is controlled by the available food supply so if you see a tank overrun with these little guys is due to the abundance of algae, nothing else. Control the algae and you'll control the Asterina population. I personally quite like them and have never had an issue with them taking over or eating any soft coral polyps.

Technically they are not in the Asterina genus, they are in Aquilonastra.

 

[MaxTremors]

You should really not speak before you think due to your ignorance, i have a 5.5 gallon that he is in, youre real smart telling a newer person to the hobby to keep something that can possibly infest my tank and eat my corals. I'm not doing it because im spoon fed, im doing it for the benefit of my other pets that i have in that tank.

They will not infest your tank or eat your corals. Their population can get large if you overfeed and have nutrient spikes that cause algae blooms. Despite people always claiming that they eat corals, in my decades in the hobby I’ve never seen it, and I’ve never seen anyone produce any actual evidence that they do. This person actually gave you good advice. People new to the hobby are, for some reason, taught to be paranoid about hitchhikers, which leads to less healthy, less diverse, less interesting, sterile tanks. The vast majority (like 99%) of hitchhikers are manageable, and like 90% are harmless if not beneficial. It’s your tank, so do what you want, but these are not the threat people claim they are.

 

[monkeyCmonkeyDo]

It's an asternia star. Yes they will multiply and yes they will sit on top of your zoas and palys. Making the individual polyps retract as they eat them. Lol.
Little buggers.
Remove.
D

 

[Jedi1199]

I'm wondering if this is an asterina star or not and if it is i'll remove it immediately

I am not 100% sure that is a true (what we refer to as Asterina) star. It looks a little too defined in its shape. In my personal experience, Asterinas tend to be a little bit more misshapen. 1 arm shorter than the others, possibly a 6th arm, that kind of thing.

I agree that Asterinas are useful and harmless part of the system. I did my best to keep as many of them as I could on my upgrade build. Why wait to get a whole new batch to populate when I already had them right?

As I said, I am not going with a positive ID here myself. It may or may not be. I will leave a final decision to those who know better than me.

 

[Sump Crab]

I like them. Never had any problems from them over the past 20 years.

 

[monkeyCmonkeyDo]

Mind blowing that people think these are a positive beneficial influence on your biodiversity as they call it.
Star fish are predatory by nature and eat a lot of microfauna...including zoanthexllee in your soft coral.
D

 

[Sump Crab]

Mind blowing that people think these are a positive beneficial influence on your biodiversity as they call it.
Star fish are predatory by nature and eat a lot of microfauna...including zoanthexllee in your soft coral.
D

Anecdotal evidence suggests they are harmless in my systems. Plus I enjoy seeing one crawl by every once in awhile. Very cool little creatures IMO.

 

[monkeyCmonkeyDo]

I used to think the same thing till they multiplied and had consumed whatever fed them. They will sit on top of zoas. I can only share my experiences. It's your tank as is it the op's
D