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Aug 26, 2008
Ive heard starfish are good for a clean up crew in an octo tank but Im not too sure which a good one would be accaptable. I was looking at the Red General Starfish, Elegant Seastar - Fromia Starfish, and the serpent starfish.

Can anyone tell me if these would be compatible or how they would benifit the tank. sorry, I dont really know much about starfish.

Avoid the general starfish or any of the similar species. I found my first O. hummelincki getting munched by my bahama starfish, don't know for sure if it was the cause of death or just cleaning up but I wouldn't risk it again.

Serpents should be fine. They benefit the tank by cleaning up the little pieces of food that get left behind after a meal.
i think my serpent loves my octo. it is always hanging out by where the octo is. like am stated, i always assumed it was scavenging pieces of food.
I am a big fan of the Thorny seastars for my octo tanks. They don't let scraps stay in the aquarium and are visible almost all the time. They come in several colors but the bright orange really adds color. I have 2 in the 60 but would not put more than one in anything smaller AND we add a small bit of frozen food daily to the tank for these and the serpents.

I also have a red brittle star in two of my tanks that I am rather fond of. Unfortunately, I am not sure how much clean-up they do and we feed them Cyclop-eze but they are intresting, often seen (at least at feeding time).

The serpents seem to like to live very close to the octos den and help keep it clean (I swear my female mercatoris moved out of her den for a day - prebrooding - just to allow her private maid to come in and clean). I keep serpents in all but my only "fish" tank and they are interesting to watch at feeding time but are rarely seen other than when they are grabbing food.
Sounds good and depending on what else you put in the tank, you can double that if you feed. In OhToo's 60, I have two serpents, one brittle and two thorny's but no other clean up crew to speak of. We do feed Cyclop-eze daily to the tank and make sure everyone has enough to eat. I think you will find you enjoy the thorny's more than any of the others because they are so bright and so active. I know the fromia are written as THE recommended starfish for an aquarium but I have tried several in different, stable aquariums and only succeeded in keeping them alive a month longer than the pet store. I have never lost a thorny and only a couple of serpents (I have many scattered about in my 7 tanks and only the red have given me a problem and only after two or more years) Wait until your tank is fully cycled before adding the seastars though, don't make the mistake of thinking they are like snails. They cannot take harsh changes, especially in PH and will fall victim to new tank syndrome if the tank is not stable. They are not aggressive towards conspecies (or any others) so they can be added at any time after the tank is mature.

One exception is the green serpent that looks somewhat like a cross between a serpent and a brittle. They have a reputation for becoming aggressive when they get older and can get huge. I have had one for many years (the oldest critter I have) and he has not caused problems but Mr. Green Jeans was removed from OhToo's tank because he seemed to be intimidating the octopus. He had never been a problem (in fact he kept loosing arms and was continually being quaranteened for his own safety) but now that he is growing and maintaing his arms, we felt better safe than sorry.
I've never heard of them eating fish, but a "little known secret" that EVERY LFS and online vendor seems to "forget" to tell you is that most will eat corals. Though it all depends on the animal of course.
I would consider a chocolate chip star to be on the no-no list. Similar to my bahama star, vorcacious meat eater.

I wouldn't waste money on the sand sifting star. Doomed to starvation.