Blue hippo changing color?

[SmyrnaReefer]

I was looking at someone's tank tonight. It was a 225 with 2 4" hippos. As we ere leaving, the black stripe turned yellow and the freckled area of its face. Has anyone seen this before? Could it be s territorial thing because there is 2 in the same system.

 

[Dowtish]

I guess no one has.

 

[BillyC]

All blue hippos do this. It's an aggressive reaction. Mine does it when he fights with his own reflection?

 

[KSzegi]

Mine does it too but it really doesn't seem like an aggressive reaction to me ..... never does it at his reflection or anything. Typically when he does it though he has one of his crazy half-hours ..... zipping around the tank, shaking his tail and generally acting like a goofball. When I had two - both would do it but were never aggressive towards each other, now I have only one large one and he goes in spurts when he will do it every evening for awhile and then not for a week or two .....

 

[Badspstank]

Hell I do it when I see my electric bill lol sorry