What is this Slug?

[Caleb423]

Well this is the second time I have seen this little guy, about 3 days ago I turned my lights on early in the am (still dark outside) and saw this slug one of my rocks. Usually I turn the on around 9 am so there is a little bit of sunlight in the room before the lights are on. This morning I turned them on early to see if I could get a photo of him and sure enough he was in the exact same spot as before.

He is about 3/4" long, triangle markings on the side, a very light gray color (almost white), and retreats and the first signs of light.

Here is a photo!

 

[Reefphd]

Most sea slugs are predatory, not all, most.
It's impossible to ID from that picture, but the better question is are any of your corals suffering?

Has the slug been in there a long time?
Could be harmless.

 

[kashman100]

Could be a type of nudibranch. Some are smooth on top

 

[Caleb423]

None of my corals show any signs of them being picked at, I am assuming it is an algae grazer because the location I have seen it in is not near any corals, but on a rock with a little algae growth.

As far as how long it has been there it is hard to say, I bought this tank used and it had been running for two years prior to me buying it. Due to its size I would say a while because if it where a hitch hiker from anything I brought in it would have been very small for me not to notice it. Plus I have qt'd all new frags with exception of one.

 

[Caleb423]

The raised triangles on the side of the body seemed odd to me. I have never seen any like it, but I'm by no means an expert

 

[Tahoe61]

Could be a Chiton.

 

[Caleb423]

Tahoe61, thank you! I think you are correct, is there anything I need to look out for?

 

[Reefphd]

None of my corals show any signs of them being picked at, I am assuming it is an algae grazer because the location I have seen it in is not near any corals, but on a rock with a little algae growth.

As far as how long it has been there it is hard to say, I bought this tank used and it had been running for two years prior to me buying it. Due to its size I would say a while because if it where a hitch hiker from anything I brought in it would have been very small for me not to notice it. Plus I have qt'd all new frags with exception of one.

Well, that's just plain cool. It's rare when you get a beneficial sea slug.
Maybe it's Sea Hare?

 

[Tahoe61]

Tahoe61, thank you! I think you are correct, is there anything I need to look out for?

You're welcome.

I consider them to be an asset, they are excellent algae eaters. There will always be the rare case reported of Chitons become an opportunistic feeder but I would enjoy this hitch-hiker and not give it a second thought.