I've always fed my peacock bass frozen krill... and they've always loved it. But recently i've noticed them eating a piece, spitting it back out, eating it again and spitting it back out and leaving it. Almost as if they dont like it anymore or have lost intrest. They still love to eat all the other foods that they usually eat, like pellets and blood worms, but not the krill. ANy ideas? or is it just part of there behavoir?