No problem. I sometimes wonder whether fish evolve at all from a "survival of the fittest perspective" or whether they just survive due to sheer numbers. I suspect it is more of the latter on the basis that survival is more luck of the draw (did the fish end up where food is bountiful and be lucky enough to be on the side of the school opposite that from which predators approached, etc.) than conscious action taken by smarter, faster, fitter, etc. fish.
I also think this is why fish seem just to up and die in our tanks without warning or showing signs of a problem. One day they are swimming and eating, and the next day they are dead. Nature probably has conditioned them hide all evidence of sickness or injury (to the extent possible) so as not to be singled out for predation. E.g., it is probably not a good idea if a fish doesn't feel well for it to go lay on the bottom of the ocean for a while, so it continues to act normal.
