So, I decided to switch Texas and Takoda's tanks because they were looking bored, and Texas started nipping his fins (he took a BIG chunk out of it today). Texas only nips his fins when he gets bored, and I didn't have time to rerarrage the tank. Texas loved his tank, he is used to a black background so he doesn't flare, and he loved the leaf cover in Takoda's tank, while on the other hand Takoda HATES the black background on Texas' tank. He's been flaring at it for about 5 hours now, and I don't want to change them because I don't want Texas to nip his fins. I've just removed the black cover (barely got home), the tank does not look as pretty but I guess it will have to do. :( Is there a way I can get him used to it? He is a feisty bugger and hates all fish in his path (much like Texas,

) and he's really enjoying the tank when not flaring, he eats small ramshorn snails and races past the plants.
Please help!
Thanks! :)