They live in quiet water and swim or creep about slowly through submerged vegetation in search of food. They feed on various small aquatic animals. They can also swim rapidly under water. The adults are primarily scavengers. These oval black convex beetles vary in size and are often quite similar to Dytiscids.
Adults are primarily scavengers.
They carry a silvery film of water below. They swim and move slowly. Use of yellow bulbs, reducing wattage, or turning out the lights after night swimming may help some. A good net may be the most practical way to remove the bugs from the water. Pool disinfectants, such as chlorine, are of limited value in aquatic insect control.