Weird little things taking over my rock

[Mordkanin]

What on earth are these? They're spreading like CRAZY all over my rock.

 

[littlefoxx]

Starfish?

 

[Mordkanin]

Starfish?

No. They're not starfish. They're attached at a point to the rock.

 

[littlefoxx]

Weird. Are they hard or soft?

 

[ISpeakForTheSeas]

Colonial tunicates - they’re harmless, but can sometimes be a bit invasive :

Haha, yeah sorry - that's part of why I threw in the TLDR at the bottom there. Here are some photos of colonial tunicates with similar body structure (and some with - from what I can tell - similar coloration) to help decide if it is a colonial tunicate:

(The two above images are from here: https://www.mdpi.com/1424-2818/14/11/977 )

And the link below has a bunch more pics (some are different colonial tunicates like above, some are solitary tunicates):

Ascideacea

Ascideacea

www.floridamuseum.ufl.edu

What are these?

I noticed the growing on the back. Picture one looks like snails but the other picture that looks like flowers don't have a clu. Please help. Thanks

www.reef2reef.com

 

[Mordkanin]

Thanks. I was like 90% sure that was the case, but didn't want to taint the response.

I do not like them. One is growing on the foot of a troubled rock flower anemone that keeps moving around. I'm gonna try to remove that one tomorrow.

Can I do anything about them, other than hope that corals crowd them out?

 

[ISpeakForTheSeas]

Thanks. I was like 90% sure that was the case, but didn't want to taint the response.

I do not like them. One is growing on the foot of a troubled rock flower anemone that keeps moving around. I'm gonna try to remove that one tomorrow.

Can I do anything about them, other than hope that corals crowd them out?

They should scrape off pretty easily (though getting one of a live nem could be challenging); otherwise, I’d imagine smothering them with kalkpaste or using other Aiptasia/Hydroids removal methods should work.

 

[Fishy888]

Thanks. I was like 90% sure that was the case, but didn't want to taint the response.

I do not like them. One is growing on the foot of a troubled rock flower anemone that keeps moving around. I'm gonna try to remove that one tomorrow.

Can I do anything about them, other than hope that corals crowd them out?

You can send me some. I’d love to have some tunicates.

 

[jabberwock]

I am not sure those are colonial tunicates. Mostly because they are not being colonial. They are all spread out and seem to be individuals. Here is a picture of my experience with colonial tunicates.

 

[ISpeakForTheSeas]

I am not sure those are colonial tunicates. Mostly because they are not being colonial. They are all spread out and seem to be individuals. Here is a picture of my experience with colonial tunicates.

They are definitely colonial tunicates (as are yours) - you seem to have one or a few larger colonies that close together; the OP has several smaller colonies that are more spread apart.

Each opening around edge of your tunicate colony (the holes around the little canals/trenches in the skin of the colony) is the oral siphon of a zooid (a single tunicate specimen in the colony, hence the name, colonial tunicates):

the little funnels around the outside are the oral siphons (the incurrent siphons - also known as buccal siphons) and the large mouth in the center would be the common cloacal siphon (the shared outcurrent siphon). So, the water would flow in through the oral siphons (then out through the individual zooid - each tunicate in the colony - atrial siphons which are hidden inside the common tunic - which is basically the skin shared by the whole colony) to the common cloaca and out through the common cloacal siphon.

Edit: Some good colonial tunicate anatomy explanations in the link below:

Untitled 1

 

[jabberwock]

A limpet ate mine... I had then for a few months. Sad that they are gone.

And thank you!

 

[Mordkanin]

I did a big water change today, and noticed with them retacted that they have a large purple 'base' to them, sort of like a star polyp coral.

Bonus pic of my RFA next to one, which isn't doing so well. He's shrinking and moving a lot, and I'm not sure why. Not enough light, maybe? He's very near the bottom of the tank, but he moved there on his own, traveling down from the top of the rock I put him on (He was on the sand next to it for a couple days before starting to climb back up).

He managed to dislodge himself from the one that I thought might be attached to him yesterday.

 

[ISpeakForTheSeas]

they have a large purple 'base' to them, sort of like a star polyp coral.

Yeah, the color of the base/tunicates varies, but that encrusting base is how they spread (so pretty similar to GSP). You actually have the clearest pics I’ve seen of the base though - most pics show more mature colonies with lots of zooids and very little unoccupied mat space for new ones:

 

[Mordkanin]

You actually have the clearest pics I’ve seen of the base though - most pics show more mature colonies with lots of zooids and very little unoccupied mat space for new ones:

Then you might like this picture of the back of one that's growing on the glass.