ID Help Translucent Tube Colony

[Mirror222]

Any ideas. I have watched one colony slowly grow out of the sand for about 2 months to about the size of a quarter and 1/4 inch tall. Then in the last 2 weeks 8 new colonies have appeared and all rapidly grew to the size the first one took 2 months to reach. they don't react to touch that I can tell and I have never seen anything move but the hollow tube structure has me puzzled. My tank is 6 months old and only has a cleanup crew. About to get my first fish so curious friend or foe?

I apologize for the photo quality. I need a macro lens for my phone.

 

 

[Tired]

Oh, interesting! Those are some pretty good photos. 

 

I would say this is probably a sponge, or a tunicate. Leaning towards sponge if it doesn't react to anything. If you poke it with something, is it stiff or springy? 

 

Pretty much everything in the "weird-shaped structure of tubes with no animal inside" category is harmless. Some sponges can become pests due to growing too fast and climbing over corals, so you may want to keep half an eye on these. If they start going near solid structures, I would prune those ones back. Any that are in the sandbed should be relatively easy to remove. As a general rule, sponges should be kept to places where you can easily remove parts of them when needed. 

 

Are there any that are separate from the others? I would be curious to see, if you dig into the sand around one of these, is there a lot of it under the surface? It could be that the new ones grew faster because they have 'roots' established already. 

[Mirror222]

TLDR - Thanks for the help Tired - some kind of Sponge.

 

They are springy to the touch so a stiff soft tissue that still holds up out of water. So of course that means I dug one up and its about 50/50 where half is under sand and half is exposed. no real root as far as I can tell, the ends appear to be above sand, below sand looks like tangled string trapping sand grains, the clump is ball shaped.  I can not see runners but the growth pattern is spreading out so runners make good logical sense from observations. plus my fingers/turkey baster probably destroyed any runners in my collection attempts as it seems pretty delicate.

 

First attempt was with fingers and that one disengaged, second try was by sucking with turkey baster, that worked. but it is so small in the jar I can not focus the camera on it. 

 

Follow-up - I spent a good 20 minutes looking up translucent sponge photos in image search after Tired's reply and followed up on his suggestions and leads. Found something very similar looking from another reefing site ID chain but theirs grew on rocks, they described the same low to mid lighting and low to moderate flow area of the tank. It was also thought to be sponge. so I think we can file this one away under likely Sponge.

[Tired]

You'll find many pale-colored sponges that grow in similar habitats, there's an unknown but massive number of species. They're neat animals. The rock-clinging variety I have has grown large enough in spots that it can visibly pump water through itself, stirring small particles that drift near it when the tank pumps are off.

 

If I were you, I would probably leave one clump and see what it does. It would probably be pretty tricky to get out of the tank for good, anyway- I'd wager all the little broken bits will happily continue to grow. Good thing sponges don't sting. I've read about some of them releasing chemicals to interfere with coral growth, but I believe that's generally only a problem when you have a ton of sponge mass in your tank, and often not even then. Plenty of reef tanks have sponges scattered around with no problems. In fact, I'd wager just about every mature reef has at least one sponge species in it somewhere, and I guarantee all the ones with live rock have more than one species. 

[Mirror222]

I kept my original and the other large groups that are up front undisturbed, I only went after 2 that were by the rock work in back for science! Original intention was 1 but my fingers kind of crushed it. I still have 6 left, 5 of which are about quarter sized. I am going to keep watching them grow out. Two of the groups started to merge in the last day or two, That is the second photo above, you can see it goes off to the left out of frame where another similar group is growing. The cluster is technically in a good spot in the sand bed, it could get fist sized before it touches any rock work. I will stop here as I could ramble on for a while. 🙂

[Tired]

Sounds cool. If they do anything notable, I'd love an updated picture.

 

It might also be interesting to place a shell or bit of rubble right next to one clump, and see if this is a kind that will grow onto the rockwork at all. If it's really involved with wrapping into the sand, it may be a species that stays in the sand for good.