clown swiming on an angle

[freewilly2]

my clown fish is swimming on about a 70 degree angle and i dont know why he looks 100% normal and is eating fine. paramaters are nitries:0
nitrate:0
ammonia : 0
ph: 8.3
salinity: 1.023

dont know whats wrong

 

[kevin2000]

Sometimes fish will ingest air which makes it difficult for them to maintain balance ... more common if your feeding flake or something that floats on the surface. If you think this applies to your fish then the problem should "pass" on its own and you should consider switching to a food source that doesn't float.