Is this a coral ?

[rc8t6353]

What's up everyone. Today while doing a water change, I noticed this on one of the rocks. I've seen it before but never with the feathery extensions out. Before, I just thought it was some kind of stubborn algae. But while blowing off the rock it's on, it reacted, and retracted all the feathery stuff lol. Any help is appreciated!!

 

[blaxsun]

Does it look like this under white lighting?

 

[Mikedawg]

Research hydroids using pic taken under white light

 

[rc8t6353]

Does it look like this under white lighting?

Sure does but greener

 

[blaxsun]

Sure does but greener

That one is a colony of aiptasia, so hopefully it's not that (but I couldn't see enough detail in the image you posted).

 

[WheatToast]

Does it look like this under white lighting?

That one is a colony of aiptasia, so hopefully it's not that (but I couldn't see enough detail in the image you posted).

I think those are yellow polyps (Parazoanthus sp.), which, to my knowledge, are very fast-growing and potentially invasive.

Research hydroids using pic taken under white light

+1 on hydroids. My thought was that OP has colonial hydroids, which are differentiated from Aiptasia and similar-looking polyps as they grow from tubes:
https://www.reef2reef.com/threads/are-we-sure-these-are-colonial-hydroids.797406/

 

[rc8t6353]

I think those are yellow polyps (Parazoanthus sp.), which, to my knowledge, are very fast-growing and potentially invasive.

+1 on hydroids. My thought was that OP has colonial hydroids, which are differentiated from Aiptasia and similar-looking polyps as they grow from tubes:
https://www.reef2reef.com/threads/are-we-sure-these-are-colonial-hydroids.797406/

I agree with you. I looked up the colonial hydroids and they look exactly like them. I need to learn how to take better pictures lol. Anyways, I didn't want to take any chances of them spreading since I just kinda got my tank back on track. I removed the whole rock and replaced it with a piece from my leftover rock. Thank you all for your help!!

 

[Slocke]

Does it look like this under white lighting?

Yeah those are parazoanthids. Grow like weeds but a coral not aiptasia but definitely look and grow similarly.

 

[damsels are not mean]

I have a colony of hydroids like this. Mine are green fluorescent around the mouth and seem to be photosynthetic (they won't grow in the shade and corals have defeated them by shading).

Mine are not aggressive. I can't imagine many are. They do spread but kinda slow. No faster than zoas. Corals seem to step over them so I don't worry.

 

[EeyoreIsMySpiritAnimal]

I have a colony of hydroids like this. Mine are green fluorescent around the mouth and seem to be photosynthetic (they won't grow in the shade and corals have defeated them by shading).

Mine are not aggressive. I can't imagine many are. They do spread but kinda slow. No faster than zoas. Corals seem to step over them so I don't worry.

You're lucky

 

[damsels are not mean]

You're lucky

Ill take a picture tomorrow with lights on. It started in one spot then got smothered by a leather now it spread to a spot in the middle of the tank but these pink zoanthids are starting to cover it up.

 

[vetteguy53081]

Yes need opics under white lighting as I too thought yellow polyp coral but impossible to determine under heavy blue lighting

 

[EeyoreIsMySpiritAnimal]

Ill take a picture tomorrow with lights on. It started in one spot then got smothered by a leather now it spread to a spot in the middle of the tank but these pink zoanthids are starting to cover it up.

There certainly are species that aren't a potential plague, but it seems more often we hear about the bad kind.

Sort of like the 2 aiptasia I had in a corner of my display for almost 3 years that never spread (and were quite pretty )... Nobody would worry about how to eradicate those

 

[damsels are not mean]

There certainly are species that aren't a potential plague, but it seems more often we hear about the bad kind.

Sort of like the 2 aiptasia I had in a corner of my display for almost 3 years that never spread (and were quite pretty )... Nobody would worry about how to eradicate those

It's been the same for me with vermetids. I have a bunch of small ones that bloomed and then crashed and now there are just a few here and there. Never harmed a coral or anything. There is a single huge one in the back of the tank, presumably needs a mate to reproduce but has none. That one probably would irritate corals.

 

[EeyoreIsMySpiritAnimal]

It's been the same for me with vermetids. I have a bunch of small ones that bloomed and then crashed and now there are just a few here and there. Never harmed a coral or anything. There is a single huge one in the back of the tank, presumably needs a mate to reproduce but has none. That one probably would irritate corals.

I have a lot of the little ones too... No idea if many tubes are even inhabited anymore but they never put out a noticable net. But I have a few larger ones that did/do... Luckily the flow takes the mucus nets away from the neighboring coral.

 

[Tavero]

I agree with you. I looked up the colonial hydroids and they look exactly like them. I need to learn how to take better pictures lol. Anyways, I didn't want to take any chances of them spreading since I just kinda got my tank back on track. I removed the whole rock and replaced it with a piece from my leftover rock. Thank you all for your help!!

These aren't hydroids though. Strangely everyone here is indentifying them wrong all the time.
They are sessile jellyfish. When they release swimmers they look the same as my profile pic.

 

[damsels are not mean]

I have a lot of the little ones too... No idea if many tubes are even inhabited anymore but they never put out a noticable net. But I have a few larger ones that did/do... Luckily the flow takes the mucus nets away from the neighboring coral.

Yeah when I stir up a storm in the tank I notice thin nets from some of the little tubes. The big one in the back has a real net though.

 

[EeyoreIsMySpiritAnimal]

These aren't hydroids though. Strangely everyone here is indentifying them wrong all the time.
They are sessile jellyfish. When they release swimmers they look the same as my profile pic.

No, what you're calling jellyfish are the Medusa stage of this type of hydroid

 

[damsels are not mean]

These aren't hydroids though. Strangely everyone here is indentifying them wrong all the time.
They are sessile jellyfish. When they release swimmers they look the same as my profile pic.

Honestly I thought that is what a hydroid is?

 

[EeyoreIsMySpiritAnimal]

No, what you're calling jellyfish are the Medusa stage of this type of hydroid

Hydroid | Characteristics & Life Cycle

Hydroid, any member of the invertebrate class Hydrozoa (phylum Cnidaria). Most hydroids inhabit marine environments, but some hydroids have invaded freshwater habitats. Hydroids may be either solitary or colonial, and there are about 3,700 known species.

www.britannica.com