What is this white... thing? Sponge?

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Sorry for my camera's poor quality but I work at an aquarium and have observed this white organism grow among these palys for over a year now. It's white and branching and seems to be composed of hollow tubes. (Don't tell but I broke a portion off to take to my home tank.) I'm guessing it's a sponge of some variety, but that's not an organism I'm particularly informed upon.

 

[ISpeakForTheSeas]

Sorry for my camera's poor quality but I work at an aquarium and have observed this white organism grow among these palys for over a year now. It's white and branching and seems to be composed of hollow tubes. (Don't tell but I broke a portion off to take to my home tank.) I'm guessing it's a sponge of some variety, but that's not an organism I'm particularly informed upon.

Unless you’ve seen something living in it, I’d guess you’re right that it’s a sponge of some kind (though I’m not sure what kind). If those palys are constantly closed up like that, I’d guess the sponge produces some mild anti-coral chemicals, but it doesn’t look like it’s actively smothering the palys - it looks like it’s just outcompeting them for the space. The good news is that that means it’s probably not highly invasive, but if starts growing in your tank you may need to control it a bit so doesn’t hurt any of your corals (note that I say if here for two reasons: one, some sponges do well in some tanks but not others [I suspect this is in part due to bacterial differences between tanks and in part due to organic nutrient differences between tanks] and they sometimes have some difficult care requirements; and two, not all sponges are capable of reproducing/regenerating from broken off pieces, so it might not have a chance to grow from the piece you took).

Let us know how it does!

 

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Thanks for your great reply!
So the palys were closed up because I had been fiddling around with the sponge stuff before the photo. Foolish on my part! But they have definitely been growing happily with each other for my duration at this job, so they don't appear to have any animus towards each other
And yeah, there is certainly a chance it won't make it in my tank for whatever reason. I tried anchoring it among some rock in my tank but it's pretty brittle stuff. So who knows but I'm just fascinated by sponges, tunicates, etc.
In fact I would love to one day have a tank dominated by that kind of stuff! (If you know of any threads here or elsewhere where people have done that, I'd be fascinated to read more!) I had a previous tank with some blue photosynthetic sponge and it was really taking off at the point I had to sadly take that tank down. Now I have a pretty lousy light (Fluval 13.5's stock light) and no particular way to find more of that organism besides.
I'll try to remember to update this post if anything cool happens.

 

[ISpeakForTheSeas]

Thanks for your great reply!
So the palys were closed up because I had been fiddling around with the sponge stuff before the photo. Foolish on my part! But they have definitely been growing happily with each other for my duration at this job, so they don't appear to have any animus towards each other
And yeah, there is certainly a chance it won't make it in my tank for whatever reason. I tried anchoring it among some rock in my tank but it's pretty brittle stuff. So who knows but I'm just fascinated by sponges, tunicates, etc.
In fact I would love to one day have a tank dominated by that kind of stuff! (If you know of any threads here or elsewhere where people have done that, I'd be fascinated to read more!) I had a previous tank with some blue photosynthetic sponge and it was really taking off at the point I had to sadly take that tank down. Now I have a pretty lousy light (Fluval 13.5's stock light) and no particular way to find more of that organism besides.
I'll try to remember to update this post if anything cool happens.

Good to know with the palys - so yeah, that sponge seems like a great candidate for keeping then! I actually have a thread* asking about sponge dominant tanks here on R2R - haven’t found anyone with a sponge dominant tank yet, but there are a few people who intentionally keep them and tunicates.

I know a few places carry red and purple photosynthetic sponges, not sure about blue though (I think I’ve seen a place list the purple one as blue though, if I remember correctly).

Edit: forgot to include the thread link.
* https://www.reef2reef.com/threads/any-sponge-dominant-tanks.916637/