Aquarium Water Filler — clear, simple water topping and automatic level control Key benefits Maintains stable water level automatically: the unit starts and stops on its own, eliminating the need for constant monitoring during normal evaporation or small refills. No electricity required: fully automatic operation means reliable performance without power cords or pumps. Easy to install and adjust: designed to attach directly to your aquarium tub for quick setup and convenient use. What it is and how it solves problems Function: an aquarium water filler that refills tanks and helps maintain a healthy environment for fish by keeping water levels consistent. Problem solved: prevents stress and harm to fish caused by fluctuating water levels and reduces the time spent on routine top-ups and small water changes. Standout features: automatic start/stop operation with no external power needed, simple attachment, and an adjustable design for flexible positioning. Important attributes Adjustable: shaft can be positioned to suit your tank setup. Materials: metal shaft and acrylic component. Compatibility note: the shaft is made of metal and is not suitable for water and seawater. (Please verify compatibility with your tank before use.) Performance: automatic, mechanical start/stop—no electricity required for normal operation. Practical use scenarios Home aquarium evaporation control: attach the filler to the tank rim to automatically top up evaporated water and maintain a steady surface level. Routine water changes and refills: use during partial refills after cleaning to add water smoothly without splashing or stressing fish. Short trips or busy periods: provides reliable, hands-off maintenance when you cannot attend to the tank daily. What to expect on installation and operation Simple attachment to the aquarium tub for immediate use. Adjustable positioning to fit a variety of tank rim configurations. Automatic mechanical operation—set up once and let the unit manage routine top-ups. Note Materials listed reflect the product construction: metal shaft and acrylic element. The product description specifies the metal shaft is not suitable for water and seawater; please confirm this detail against your intended application before purchase.