knifefish faded? please help!

[mclb72]

Hi, just wondering if anyone know why my tiger knifefish's stripes are fading specifically around his stomach and underside. Just noticed it happening in last week. My water parameters are good, with low nitrate, nitrite, ammonia. Tank is well established over a year. Please help he is my pride and joy. This pic is before fading started, no newer pic he is very camera shy.....thanks,
u guys are great!.. Mike

 

[Aqua Sanctuary]

I am sorry but i would like to see a new pic of him. Thats really the only way to tell what the "fading" is.