(ID) White growth(s) on an isolated part of the rock.

[rhostam]

Hi,

I thought I was prepared to see most of the common things that grow or hitchhike into a reef aquarium in my aquarium, but I was wrong. Today I was enjoying my tank and doing one of the daily inspections. I noticed something I haven't seen before... I tried searching for an ID on the 'nets but I am not sure how to describe it.

Description:
White/ translucent growths on the surface of a portion of my rockscape. The only thing I can compare them to is HUGE ich cysts, but their silhouette also reminds me of eggs or planula larva (?).

I see some of these things caught in the GHA and it is also growing or attached to areas covered by coralline algae. I've pointed out some obvious spots in the pictures. I've Xd out examples of spiroid worms in the vicinity for comparison.

Thoughts? It isn't growing ALL over the rock. More or less the isolated section and it's most apparent in areas of that rock that are have slightly more protection from the flow.

Thanks in advance.

Finally, a YouTube video that's been pixelated beyond usefulness I think. But if it helps...


It is growing on this area/side of the aquascape:

 

[Reefing102]

Perhaps colonial Hydroids? I'm honestly not too sure.

 

[rhostam]

Perhaps colonial Hydroids? I'm honestly not too sure.

Eek.

 

[rhostam]

Any night owls online with suggestions?

 

[EeyoreIsMySpiritAnimal]

Do they move? I honestly haven't seen anything quite like that... Maybe tiny sponges?

 

[rhostam]

So an update: Almost as quickly as they came (at least I think!?), they vanished.

My guess is indeed some kind of small colony sponge as you suggested.

Thanks for those that tried to help ID.

 

[vetteguy53081]

May be sympodium. if not, possibly dictyota which is a nuisance type algae