My neighbor has an old sink that is about 2ft deep & almost as wide that we are wanting to turn into a bait tank to hold shiners in between fishing trips. What are my options to use for a simple filter? I seen one tank on here that the piping came up over the top & the water simply passed through some type of filter in route back to the tank. It almost just looked like some sort of a/c filter material. I need some ideas...Thanks!