itty bitty star fish

so i was sitting on the floor one night staring at the tank and saw what looked to be an itty bitty star fish on one of the rocks. Thought I was crazy and went to bed. the next morning it was not there. Flash forward 3 weeks and it made a reappearance! I am quite excited to see it--It has survived!!--but is it a pest? I hope not, but am not sure. It is about the size of the tip of my pinky, 6 legs and is beige. any ideas? possibly asterina, but it does not look like the pic I have found.

 

Probably harmless

 

It probably doesn't look like the pic of an asterina you found because there are tons of species of Asterinas and they all look different because their legs are varying in lengths because of splitting. They are almost never pests but peaceful algae eaters that will emerge from the rocks at night and help clean the rocks and glass of algae only to disappear back into the rocks when the lights return. If you see them always hanging out around and on the corals than you may have a problem, however, even if they are just on the base of corals, they may well just be eating algae that has collected there.

All in all, don't worry, be happy. Asterinas are generally good.

 

You have Asterina stars. Harmless little buggers. If you have one.....you have many. Some people go for total eradication.....I don't. If mine get out of hand, then I will scoop out what I see and leave the rest. No big deal.....just consider them part of your clean up crew.

 

I have one also--It came on my chaeto algae--The lfs had a bunch of them in his reef display. They eat algae and ditritus--they are good.

 

yeah! He was a cute little thing! Thanks guys!

 

Wow, I was just coming here to ask this question. I have quite a few of these and thought they were pretty cool.

One question, do they eat coraline? I know they eat hair algae as I have one that is about 3/4 of an inch across and I have seen the path it leaves in the algae on rocks. My tank is still fairly new and I'm working through a hair algae bloom. I also have a few rocks with coraline that has white or light pink circles in it about the size of the small sea stars and was wondering if that was where the stars were feasting.