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Green Brittle star


May 9, 2005
Has anyone kept green brittlestars with bimacs? I know they can be highly preditory towards small fish and shrimp, but what about an octopus? My octo is about the size of a ping pong ball or golf ball when curled up, and a friend is giving away a 2" disk, 7-8" arm green brittle.


I'd say no to to the green brittlestar. First of all, there is a great size mismatch. Even if the brittlestar didn't harm your octo, he could steal its food (As I recall, Colin had some problem with this.)

Then I consulted Anthony Calfo/Rober Fenner's Reef Invertebrates, which has detailed information on almost all the species you'll encounter (and wonderful photos, too!) The green brittle starfish attacks small fishes, but it's also know to attack shrimps, bivlves and quite a few other animals. It has quite a strategy for catching the little fish, arching up on its legs and making a nice, safe looking cave. When a fish comes into the "cave", the brittle star drops down on it and eats it. This species of brittle star grows quite large (over 12 inches) and is recommended only for tanks having large fish, not for tanks with invetebrates or smaller animals.

I have a serpent star that has lived with Hermin, Ink, Inklet and now Gimpy. Funny cause when there is no octo, you never see him, but add one and he's right there camping out by the Gimpy's den.
ya i know what you mean carol. i have a chocalate chip star and 2 brittle stars and they follow the octo lookin for scraps. (he's bigger) but if they get to close hell push em out of da way.
It seems to be only the green brittle star that is a problem (Ophiarachna incrassata). Also, relative size makes a difference.

I suppose how this brittle star behaves depends on how well you feed it and whether you have other invertebrates in the tank.

yeah, the green serpents can be a real pain, i wouldnt doubt they could catch and eat a small ceph. The experinence Nancy mentioned was the brittle star constantly stealing food from a bimac i had!

having said that i really like them and have one in beside a pair of melanopus clowns :smile:
NOOOOOOOOOO! GBS (Green Brittle Stars) are very destructive! Will steal food, eat fish, RIP APART ANY CORALS TO GET AT STOMACH CONTENTS, and gets VERY BIG. Sooo... NO! NEIN! NIET! AND NOPE!
Do not get. o_O
ive got a giant (like a foot or more wide) black spiky brittle star in my reef tank that has been in the same peice of live rock for 1 year now... what if i put him in with the new octo when he gets here... is that a safe idea or are they worse than the green ones... he looks very frightening and mean...
they are nowhere near as outgoing as the green ones, and i have had them in several ceph tanks... just use common sense and don't put a huge star in with a tiny octo :smile:

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