Aquarium Glass Lily Pipe is an innovative new product that utilizes the Bernoulli principle to create suction from the water flowing out of your external filter, skimming across the water surface. This effectively disrupts the accumulation of biofilm on the water surface, mixing it back into the water column. While it doesn't remove anything from the water, it recirculates it, allowing your filter to potentially collect it, achieving a residue-straining effect. This can reduce your maintenance workload and minimize the equipment inside the aquarium, reducing the need for hanging items and various wires. It serves as a great low-visibility option, with efficient up-and-down movement in moderate evaporation conditions, also acting as a good indicator for when the tank needs topping up. The structure is simple yet highly efficient. Perfect for removing biofilm, when compared to other brands on the market with surface skimmers on the inflow pipe, they often in air into the filter when used with high-flow filters. Over time, this can generate noise and potentially damage the filter. This product offers easier flow control, compatible with different diameters of external filter canisters, such as ada, Landen, UNS 10-100 Gallon Rimless aquariums, nano tanks, as well as Eheim, Tetra, Fluval, and other filters. Made from advanced borosilicate glass,  the 17mm size is suitable for 16/22mm 5/8'' ID.