Hi, my two Chinese Hi Fin Banded Shark has not been feeding since I got them. They have become thinner and thinner. The rest of my fishes such as tetras, corydoras are feeding very well. I feed the tank with NLS and Ocean Nutrition sinking pellets and sinking algae wafers. Ammonia is 0.25 ppm.

Are these fish hardy and supposed to be easy feeders? Any Hi Fin Banded Shark keepers with tips on feeding them to share and your experience with them? Thank you.