Cleaner Shrimp Covered in Algae

[LeanneP]

So, I have this cleaner shrimp that started getting a bit of algae on him. I wasn't too worried, but this morning it is now really thick on him and he has stopped eating. I added a little iodine a few days ago hoping he would molt again but no such luck. Anyone know why this suddenly happens? Is he sick? Also forgot to mention that when he molted last time his antenna were crocked and one short. Any ideas would be appreciated.
Leanne