Key benefits Stable, worry temperature: Intelligent heating keeps aquarium water at a constant 26C, so betta and tropical fish stay in their preferred temperature range without manual adjustments. Easy monitoring: Red/green status indicator lights show when the heater is actively heating or at set temperature, making operation simple and reliable in any lighting. Safe for small tanks: 10W power is matched for 3L desktop or nano tanks, providing adequate warmth without overpowering a small volume of water. Durable waterproof construction: Crackresistant body, shatterproof exterior, and a rubbersealed waterproof mechanism reduce the risk of leaks and electrical faults for longterm underwater use. Portable power options: USBpowered design lets you run the heater from a USB outlet, power bank, or adapter for temporary setups and mobile habitats. What it does and why you need it Maintains a constant 26C to support the health and activity level of betta and other tropical fish. Stable temperature lowers stress, improves appetite, and aids recovery in sick or young fish. Eliminates the need for constant manual temperature changes and frequent checks; the heater adjusts automatically and reports status via the indicator lights. Designed specifically for small aquariums where fullsize heaters are unsafe or impractical. Its compact, lightweight profile fits neatly into desktop tanks without taking up valuable space. Key features and specifications Temperature control: Intelligent fixed setting at 26C for stable tropical conditions. Power: 10W, appropriate for approximately 3L small tanks. Indicators: Intuitive red/green status lights for heating and ready conditions. Build: Crackresistant structure and shatterproof exterior for underwater durability. Sealing: Rubbersealed waterproof mechanism to prevent leaks and electrical hazards. Power source: USBpowered for flexible use with USB adapters, computer ports, or portable power banks. Compatibility: Recommended for betta and other small tropical fish species and for desktop or nano aquariums. Practical applications and scenarios Home desktop aquarium: Use in a 3L betta tank on a desk or shelf to provide discreet, steady heating without taking up space or creating visual clutter. Travel or temporary setups: Power the heater from a USB power bank during short moves, temporary housing, or while transporting pets to maintain comfortable water temperature. Quarantine or fry tanks: Maintain a consistent 26C in small hospital/quarantine tanks or fry rearing containers where precise, gentle warming supports recovery and growth. Usage notes and safety reminders Intended for continuous underwater use in small tanks up to about 3L. Avoid use in larger volumes where the 10W output cannot maintain temperature. Observe the red/green indicator lights to confirm heating status. Follow normal aquarium safety practices when installing and powering electrical equipment near water. Use a stable USB power source compatible with the heater's power requirements. Ensure all connections remain dry and secure. This heater offers a compact, durable, and straightforward solution for keeping small tropical aquariums at a consistent 26C, with visual status indicators and USB power for flexible placement and portable use.