Fighting Starfish?

[DebbieMc]

I have a 27 gallon FOWLR tank. I recently bought a cleaner kit from a website. This included a brittle starfish. I already have a serpent star. When I put in the new starfish in the tank the other one immediately got on top of it and the new one was trying to get away while my old one pulled it back. I didn't think they were territorial. I fed my old starfish to distract him from the new one. Should I be worried? I always try to only put compatible inverts/fish in my aquarium. I cannot find anything on fighting starfish. thanks

[jeremy arsement]

What do you feed a starfish?

[SHARPiE]

I've read Brittle Stars should be added with caution? Temperament is Semi-Agressive.

"When placing Semi-Aggressive species in your aquarium, be sure to take into account the fully expanded size of this animal and provide extra room for growth. Continue to monitor the reaction of neighboring species and be prepared to move one or the other if there proves to be incompatibilities. "