Critter id...nudibranch?

[jdircksen]

Saw this guy today for the first time. Couldn't get a good picture because it under a rock. My tank is 2.5 years old and I haven't added anything for at least 6 months. I'm guessing he is some sort of nudibranch...is that correct? Is he good or bad?

 

[Hormigaquatica]

Not quite a nudibranch, but a snail. Its a Scutus (aka black limpet). Harmless algae grazers, and one of my personal favorite hitchikers.

 

[jiriki]

I used to have one... came out only at night.. I named it "Roomba". It has an internal shell.

 

[gelatin_man]

how big do they get...I think I have one of those that is like 2.5 inches.

 

[Hormigaquatica]

<a href=showthread.php?s=&postid=15706939#post15706939 target=_blank>Originally posted</a> by gelatin_man
how big do they get...I think I have one of those that is like 2.5 inches.

Thats close to the largest Ive ever seen. I think they max out around 2.5-3"

 

[gelatin_man]

I only saw him for a couple of seconds in my pond but I am pretty sure he was the same thing in the pick up top.

 

[Norm R]

yep, most max out around 2.5 to 3". I had one mutant that was pushing 4"...and never knocked anything over.