Clown fish not eating and behaving strange

[MombasaLionfish]

I have two maroon clown fish I have had them for two months in a new 60gl. About a week ago the female started acting strange first not eating then hiding in a corner and now drifting aimlessly near the surface of the tank. I have pods we thought she was eating those but now we don't. What is happening to her?
I also have two domino damsels one blue yellow tailed damsel decorator crab four hermit crabs and an astral snail. My ammonia are 0 my nitrites are 0 my ph is 8.0 and my nitrates are 15 (in the process of getting those down).

 

[kichimark]

I have two maroon clown fish I have had them for two months in a new 60gl. About a week ago the female started acting strange first not eating then hiding in a corner and now drifting aimlessly near the surface of the tank. I have pods we thought she was eating those but now we don't. What is happening to her?
I also have two domino damsels one blue yellow tailed damsel decorator crab four hermit crabs and an astral snail. My ammonia are 0 my nitrites are 0 my ph is 8.0 and my nitrates are 15 (in the process of getting those down).

Nitrates would not be a problem at 15ppm. Anything new to the tank when you noticed the unusual behavior? Does her body look different color wise?

 

[MombasaLionfish]

The snail is new. Her color is normal.

 

[MombasaLionfish]

This morning she was dead.

 

[MombasaLionfish]

What happend to her?