Precise Measurement: The measurements on the tube are precise (10ml, 15ml, 20ml, 30ml), allowing you to easily match the appropriate feeding capacity and prevent overfeeding. Warm Tips: Since the connecting part is very small, please check the envelope carefully when you receive the package, the connecting part may remain in the shipping envelope without you noticing. High-quality Materials: Made of high-quality PVC and rubber materials, safe for fish and corals. Long-lasting and durable plastic material, easy to clean, will not break like glass. Coral Point Feeder: For marine reef tanks, it is easy and comfortable to gently feed corals and other aquatic animals. It can also be used to add liquid fertilizers in freshwater plant ponds. With Extension Tube: The length is about 11 (28 cm), with a 6.7 extension tube, the total length is 17.7 (45 cm), you can clean deep, hard-to-reach areas without getting your arms wet, suitable for small and medium-sized tanks. Please measure the height of your fish tank to make sure this coral feeder fits your tank. VERSATILE: These feeding tubes are helpful for cleaning debris from hard to reach areas of your aquarium or blowing away algae that may have accumulated on the rocks.