Swimming On Their Side...

[GaryHug24]

I have 2 black phantom tetras that seem otherwise healthy but they frequently swim on their side. Mostly they do this when the light is off. Has any one seen this behavior before? all my tank numbers are good and when the lights are on they swim normally.

 

[red-devil0602]

is there another light source in the room when the light is off ie window etc mine do this if the light is off and i have my lamp on. I think they may mistake the direction of the light as the surface so change the way they swim to compensate for it

 

[furryrabbit]

yes this is in fact a tropical fish disease - i think its called shimmying - or something to that nature. google it - i had a ram with this problem and it didnt last long( sniffle )