Tiger Shovelnose, Upside down

[Motorfrog]

In the past 24 hours my Tiger Shovelnose has taken to lying upside down on the bottom of the tank.

When disturbed, he swims around for a bit but then returns to his upside down position.

Anyone have any idea why he might be doing this and if I should be worried?

He's sharing a 6x2x2 tank with a pair of Nile Tilapia, a couple of striped raphael and a sailfin plec.

Carl

 

[Lupin]

What do you normally feed him? How often? What are your water parameters? Temperature? How long has this been ongoing?

 

[Motorfrog]

Panic over, he's back to his old self again, god only knows what got into him.