Chocolate Chip Starfish falling apart

[4801472577]

Help my cc starfish was behind filter for a few days and then I just found my spider crab on top of it and it looks like this what can I do to help? Checked parameters everything is normal except nitrates are 20 and it's moving but not wanting to eat

[4801472577]

This also isn't allowing me to post a pic but it looks like one of her arms are falling apart in little cubes

[Goatonfly]

Try posting in the invert forum, might get more feedback.