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Nudibranch Hitchhiker on Sponge

I just picked up a Blue Photosynthetic Sponge (Collospongia sp.), and I found a beautiful nudibranch crawling on it after I acclimated it. I removed the nudibranch from the sponge and isolated it. I know nudis are specialized feeders, and it is probably feeding on the sponge (but I am not positive). I don't want the nudi to kill the sponge I just bought, so that is why I removed it.

I would really hate to kill this nudi if I didn't have to because it is so beautiful. Does anyone have any info on this nudibranch? Here are a few pics of the sponge and the nudibranch in question:
 
My advice, TOSS IT! Are you dipping for parasites? It may be harmless but it looks like a zoo eating Nudi. One can be cute, but in the predator free tank, the possibility of hundreds can happen!
GregH
 

Phyl

Officer Emeritus
Officer Emeritus
It is very cool and you most likely got it WITH its food source. So often in our hobby we can't keep nudi's alive because we don't know or have access to their food source. I would keep it, with the hopes that you purchased enough food for it to graze on for a lifetime!
 
I will take it dont kill it i have a few tanks set up some with sponges growing on the live rock have not found a id yet but i agree with phyl its diet is prob.sponges
 

Phyl

Officer Emeritus
Officer Emeritus
You will need that sponge that he bought it with. That is its natural diet. It is possible that no other sponge will work. They typically have VERY specialized diets, which is why we can't typically keep them alive in the home aquarium. What region is that sponge from?
 
Greg I dip for parasites with the corals I get (Lugol's), but I didn't dip this sponge. I don't know if dips are safe for sponges so I didn't dip it.

Whitebird/Phyl I was thinking about that myself. The sponge is considerably larger then the nudibranch, so the damage it does in feeding on it may be minimal if even noticable. The sponge is photosynthetic, so it has that in its favor as well as my supplemental feedings for health/growth. So this small nudi may be able to sustain itself.

Switch I have no idea what region the sponge came from. If I had to guess I'd say somewhere in the Pacific, but that is just a guess on my part. I picked the sponge up on Diver's Den. Besides for some quick care stats it didn't give me anymore information....just that it is a Collospongia sp.

Phyl I didn't kill it. I was keeping it alive until I found out more information, or if maybe anyone on here may have wanted it. I unfortunately knocked the specimen cup over that I had placed the nudi in back into my reef tank when I was feeding my NPC corals last night. I had it sitting on my tank brace (stupid place for it actually) because I was changing the water in the cup it was in every so often to keep it alive. It quickly got swept up in my tank current and slipped into the rockwork before I could get to it. I haven't seen it since.

So I'm forced to see how it pans out now anyway cause it is back in my reef tank whether I like it or not. If it is indeed eating the sponge it will be easy to catch again because its bright fluorescent orange gills stand out like a sore thumb on the blue color of the sponge. If it does look like it is killing the sponge and I catch it again I'll keep you in mind Phyl. If the sponge can handle the nudi it will be interesting to watch.

Thanks again for all the help/replies guys.
 

Phyl

Officer Emeritus
Officer Emeritus
So I guess it doesn't eat that sponge, but dines solely on Eudendrium ramosum. Where do you find THAT to feed it? Sad to think that it is destined to perish.
 
Hope all work out they are such cool lil creatures i need a blue velvet one for a flatworm problem as for as this guy maybe he eats other things keep us posted
 
Gecko and Boomer while the nudibranch I have looks similar... I do not think it is the Spanish Shawl. The Spanish Shawl has red rhinophores...mine does not.

This was posted on Reef Central, and I think to date this is the best ID that matches the nudibranch I have:
 
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