sick African Red Knob Starfish

Question
QUESTION: My African Red Knob Starfish is not looking well, He first started by hanging partially off the glass. He would only be stuck by 3 of his legs and the others would hang off.Now he lays on the botton and some of his legs are curling up. His peach colored portion is looking orange.We have only had him a few weeks. Our water quality is fine. Unless he has special needs I am not aware of. I have had a choc.chip starfish for over a year and he is fine.
I noticed someone wrote of feeding there starfish. I was told they live on the algae and detritus in the tank, is that wrong? Should I be supplementing him? Is a curled up starfish a dead starfish? please help!

ANSWER: what is the specific gravity?  You could try to supplement him with some marine spirlina or something similar... dave

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QUESTION: 1.023 is  specific gravity. pH-8.1-8.2,amon-0,nitrite0 ,nitrate20.Did a 25% h2o change yesterday. Is his curling up his legs mean he's beyond help?

Answer
We have had one of these star fish that behaves much the same way... He has been doing this for about six months... then goes through a period where he is extremely active... Your water chemistry is good and the salt content is perfect... I would still try to feed him some algae and see if he will eat that... If not... then I would just let him be.... I would not medicate the tank because of he damage the medicine would do to the bacteria, etc.... I have always tried to save everything... but in this case I think he will either make it or not... and if you weigh the impact of trying medication on the entire tank... I think you will find that it is not worth the risk of starting the tank to cycle again.  Starfish are very hardy and he may just be trying to his niche in the tank... dave