What is in my tank????

[Salt_life7]

My boyfriend and I bought our first saltwater tank recently. So far we only have a few clownfish in it, and were looking to add a few more fish. well, 6 days ago we went to a local saltwater store and purchased 2 live rocks. Almost every other day we're finding a new "something" coming out of it! I've googled what I think it might be and it doesn't seem like any of it would "hurt" my fish, but I'm afraid to invest anymore money into fish if I'm going to have bigger issues. I would like some clarifications on this issue. So far I think its Aiptasia, a asterina starfish, a bristle worm (ewww!) oh and a few snails.. also I have no coral in my tank, a lot of what I seen said my critters are only damaging to it.

 

[DanyL]

First of all welcome to r2r!

It is indeed an Asterina, and Aiptasia.
As for the bristle worm, the image quality isn't good enough for me to identify it as one.
The other anemone you circled seem to be a Bubble Tip anemone.

Asterina - They mostly harmful to corals, although they will consume anemones as well. However they usually don't do much if kept in check - you can syphon them early in the morning when they come out during a water change.

Aiptasia - I would get rid of it as early as possible because when they multiple it'll a lot more difficult to control. They can in fact sting fish and even kill them, especially if the Aiptasia is large and the fishes are small.

Bristle worms - People don't like them, but they are great CuC team if you have a sand bed.

Bubble Tip Anemone - Your clowns can form a symbiosis with it.

I also noticed the colorful rocks, it's probably fine for a fish only tank, but keep in mind they may leach stuff to your water.

 

[MoshJosh]

Descending order and left to right

Bristle worm? (If so, harmless clean up crew. Some people like others don’t)
Snail (not sure which type)
Asterina star (some say they can harm corals, others say not)
Majano anemone (pest that will spread like crazy)
Aptasia anemone (pest that will spread like crazy)

 

[ISpeakForTheSeas]

Probably a bristle worm, but, as mentioned, the pic isn't the best. Generally speaking, bristleworms are good CUC.

"Asterina" sea star (technically Aquilonastra - see the super long part of the response below). They're controversial.

Probably a Collonista snail - good CUC.

I'm not a nem guy, so I can't help with the one nem that you have a ton of, but the one with the long, skinny tentacles is typically called (likely technically inaccurately) Aiptasia in the hobby. The "Aiptasia" is considered a "pest" anemone (bad).


The super long part:
With regards to whether or not the average "Asterina" (technically Aquilonastra - Asterina is a separate genus within the Asterinidae family) 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, it might be they're eating the slime coat/mucus on the coral rather than the coral itself (see below), or they might just opportunistically eat unhealthy corals. Based on how starfish eat, it seems plausible to me that it may also be coincidental (i.e. the star goes to eat something off the coral and the coral just happens to be one that is able to be negatively effected by the star's everted stomach). Regardless, Zoas are just about the only coral I've heard about regular "Asterina" stars potentially going after (so them potentially going after a birdsnest coral is news to me).

A quote I like to refer to for this:

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.

Welcome to Reef2Reef!

 

[Salt_life7]

Thank you for the responses, you've been very informative!
As far as the Aiptasia, what is the easiest and safest way to get rid of it? I think I see about 4 in there, and the big one releases a white stringy thing sometimes.
My bristle worm has been very active this morning so I got a better pic to confirm. I guess he's good to keep the snails under control, (even though he creeps me out slightly) I've only seen 3 so far but I've heard snails can be a nightmare to get rid of. The spacing between the live rocks is about 2 1/2 inches, for a size reference.

 

[DanyL]

Bristle worm it is!

As for controlling Aiptasia, the best approach is to take the rocks outside the water and remove them manually with a small piece of rock.
I would try to stay away from using F-Aiptesia, Aiptesia-X or talk paste if possible.
Another option is to introduce Berghia Nudibranchs, FoxFace, Filefish etc, however for a new tank with just a few Aiptasias it'll be an overkill.

 

[Cthulukelele]

Berghia nudibranchs are what worked for me. Interestingly enough the majanos will actually be the harder thing to get rid of. They're at least a bit prettier though

 

[AydenLincoln]

Descending order and left to right

Bristle worm? (If so, harmless clean up crew. Some people like others don’t)
Snail (not sure which type)
Asterina star (some say they can harm corals, others say not)
Majano anemone (pest that will spread like crazy)
Aptasia anemone (pest that will spread like crazy)

The snail is a limpet or a sundial snail I believe it’s hard to tell.

 

[kevgib67]

When I have had many aptasia Berghia nudibranchs have worked for me. When I have just one I’ve just injected it with lemon juice. Asterina I just manually remove when they are out and about.