Clown fish not doing well

Labored breathing, going on its side a lot, has air bubbles coating one side. I introduced two clown fish to my aquarium yesterday, one of them eats the other hasnt had anything yet. Hanging out an inch lower than the water line. Any suggestions??

 

also looks like there is a white growth at the front of the dorsal fin. Uggg...

 

Sounds like a possible parasite. If you have a QT more him in there. Can we get more info about your set up, water parameters, other fish?

 

Here is what i have:

12 gallon Nano Cube with live rock, 1 Green Polyp Leather Coral, 2 Clown Fish, 1 Skunk Cleaner Shrimp, 3 Green Chromis, 1 Sea Hare, Snails

Looks like only one side of his gills are moving.

Ammonia is 0, PH is 7.8 and Nitrate is 20, Nitrite is 0, ppm is above 300.

 

Ammonia is 0, PH is 7.8 and Nitrate is 20, Nitrite is 0, ppm is above 300.

What do you mean by.. ppm is above 300..?
Isn't PPM= Parts Per Million ..?

Good Luck, Larry