Ok I have had this I'D shark for about a 8 months he is about 6" and in a 75 gallon with lots of current for him to swim against which he usually did till this past Friday. Now I find him sitting on the bottom not moving. Which ID are always swimming so its weird. He eats fine and my water quality is perfect. Tanks filters 17 times a hr. Lots of oxygen in the water. So I have no clue what is wrong with him. All my other fish appear fine it's just him.