Surface skimmer design, the oil slick can be separated, and the oil slick is sucked into the water basket and into the water tube, would not hurt fish and shrimp. It is easier and contributes to the photosynthesis of aquatic plants. Be made of high borosilicate glass, with high transparency and high temperature resistance, give superb appearance to your aquarium. Features: EXCELLENT APPEARANCE: Glass transparency give superb appearance to your aquarium. 2 SIZE OPTIONAL: Glass tube outer diameter 13mm(suitable for 12mm tube inner diameter of canister filter) and 17mm(suitable for 16mm inner tube diameter of canister filter). WITH SURFACE SKIMMER: The oil slick can be separated, and the oil slick is sucked into the water basket and into the water tube, would not hurt fish and shrimp. The bottom tube 360° rotate design, can control the amount of water of inlet. HIGH BOROSILICATE GLASS MATERIAL: Be made of high borosilicate glass, hand crafted, with high temperature resistance(-30° to
