Is a simple sponge filter that runs off an air pump ok for a crayfish?

i used to have a simple filter a little smaller than 5x2 in. it was just a plastic case with a sponge and some of those carbon pellets then you plug it into an air pump. is that ok for a crayfish? how do they work if there is no suction power? my crayfish is only about 2 inches long. will the filter cause him harm?