Sick Tosia queenslandensis (Biscuit Star)

Question
Thank you for your help, but we lost him.
Later that day we had put him on the substrate and he hadnt moved. My partner propped him up on the side of the glass and he just collapsed from there. We noticed the brown oozing out the hole in the top also so we assumed he had begun to break up.
We removed him.
Nitrates are fine, there is another star in the tank too which has been fine also so Im not sure what happened.
Thanks heaps for your help though :)
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-----Question-----
Hi there,
Just today we noticed our biscuit star (Tosia queenslandensis) which we have had about 3 months was not attached properly to the glass of the aquarium. When we looked closer it seemed to have brown stuff right in the middle of the underside.
We removed him from the glass and put him on the substrate where we noticed there was a small small patch which was exposed and it also had brown stuff seeping from it. What kind of illnesses can star fish get and how do we treat it?
Thank you for your time.
-----Answer-----
Hi Jaime,
   The brown stuff you saw was his stomach. Starfish can turn their stomach inside out. Probably eliminating waste. What are you feeding him? Check your nitrates. High - no good for inverts. Feed him seaweed, shrimp, fishfood, etc. by putting food on substrate and set him on top. He will love it. when starfish get sick they usually develop white spots that progress to holes and then they may even break apart. It is extremely difficult to cure a star once they show signs of deterioration. Aren't they great? I love watching mine. By the way, do not put a harlequin shrimp in with him as they feed on starfish "feet". Gerry.

Answer
So sorry you lost him, Jaime. Sometimes stars contract bacterial infections which go unnoticed until it's too late. Unfortunately, once they get ill there is not much you can do. Also know these infections sometimes take a long time to develop so don't feel like it was anything you did, he could have been sick when you got him. Sorry again, gerry.