3" Nudibranch

[BigC]

Hi,
I just sat down with a cup of coffee and surveyed my tank after a hard days work. I noticed that under one of the overhangs was a waving piece of debris. ( must get that out I thought) I looked closer and it resembled some small clove polyps I have in the tank. (only slightly different) Sat back down and took another sip of coffee, then the bloomin thing moved along the rock. Crikey a Nudibranch, get the thing out of there was my first thought. So I managed to get it into a net and placed the slug in the sump/refugium, where it is residing presently until you the membership decide its fate. I ve no idea how something that size escaped my notice.
Questions
*Are these organisms dangerous to my system in regards to corals and any other inhabitants I have.
*Should it even be given house room in the sump.
*Is it fine and I'm overreacting and should give it pride and place in the main aquarium ecosystem.
*Whats its primary diet
*What size do they grow (probably a stupid question not knowing the species involved)
Please advise.
Regards
BigC

 

[Colin_T]

Some nudibranchs eat coral, some eat sponges and tunicates, most others eat algae. Generally the brightly coloured ones are poisonous and the dull brown or green ones are harmless to handle. However, don't eat any of them because they will probably make you sick Fish don't normally bother about eating them so there is no need to worry about the fish getting sick from it.
It should be fine in the sump where it will crawl around and do its own thing. If it is a coral feeder then it will probably die in the sump but at least it won't eat any corals. They often come in on live rock and are really tiny when they first appear. Then a few months later you have a slug in the tank.
I would just leave it in the sump and see how it goes. If it is still alive in a few months then it is a vegetarian variety and you can either leave it in the sump or put it back in the main tank as a curiosity.

 

[SkiFletch]

Nudibranchs are tricky, also some sea slugs can often be mistaken for nudibranchs. Either way, these organisms typcially have a very specific diet and they will often (but not always) resemble their food. The fact that it only just now surfaced indicates one of two possibilities: First, it was in your tank this whole time living happily. If this is the case, it's likely harmless and finding food (these guys don't last too long without their food source). Second possibility is that it arrived on a recent addition as a hitchiker. Then, it's anybody's guess as to it's diet and thus its fate. If the organism's prey happens to be an extremely toxic organism (like a zoanthid eating nudibranch), its death MAY be problematic to the tank as they can concentrate the toxins of their prey in their flesh for defense. Likewise if the nudibranch/slug is very brightly colored, chances are its very poisonous.

Placing it in the refugium is an OK temporary solution, but we need an ID. Does it look anything like this?

Unfortunately, nudis/slugs are a very gray and unknown area in the hobby. There is some info out there, but the sheer volume of species and their relative rarity in home aquaria makes it difficult to point you in the right direction. Pics would really really help

 

[BigC]

Many thanks guys, I'll keep it in the sump for now keeping a close eye on the situation and see what transpires. Are they hermaphrodites, do they store sperm and reproduce at random or are the possibilities of this pretty remote. Dont want to be over-run with these things.
It's pretty much a hairy type of beast and as you say Ski it's going to be nigh on impossible to positively identify given that site list with sp and spp to contend with also.
It would remind you of small GSP rock with the polyps retracted. Red to orange in colour. I know this discription is of no consequence but I just thought I'd mention it for the record.
I will get a picture of the thing shortly and get back, even if its just for something new to view.

However, don't eat any of them because they will probably make you sick

I know I'm known as a human dusbin when it comes to food and not afraid of trying new things but hey Col I'll think I'll pass on this one.

Regards
BigC

 

[Colin_T]

However, don't eat any of them because they will probably make you sick

I know I'm known as a human dusbin when it comes to food and not afraid of trying new things but hey Col I'll think I'll pass on this one.

LOL
Ramsay's hell kitchen has a new entree

nudibranchs are hermaphrodites but you need two of them before they breed.

 

[Crazy fishes]

Big C, any chance of a picture. I was quite interested to see what it looks like. If not a general description would do. I posted a while back an ID this thread with a picture of a sea slug which at the time I thought was a nudibranch. It turned out to be a half shelled sea slug, just a small slug with a flat shell covering head end of its back. I know that they are very common in UK fish shops, not sure about US, and they are voracious algae eaters!! I removed the one I posted but since a population explosion has seen all the macros in my tank vanish (that was a lot of macros). Other than eat all of the algae they are completely harmless. Just a different possibility. Ski I also know what kill that little bit of Zoa!! It was amphipods; they spun it in those silky fibers and the green gunk precipitated on them.

Regards