Product description Key benefits Thorough, lint-free cleaning: The hemispherical PET brush head reaches curved surfaces and tight corners for consistent, no-debris cleaning without leaving fibers behind. Safe on aquarium surfaces: Moderate brush stiffness removes algae and grime while protecting glass or acrylic walls from scratches. Easy reach and control: An ergonomic long handle and double-lock telescopic rods let you clean deep tanks and hard-to-reach spots without bending or straining. Stable and reliable use: Inner-and-outer double-lock design prevents rod collapse or slippage during cleaning, so the handle length stays locked while you work. What it is and why you need it Hemispherical brush head: Designed to follow tank contours and access recessed areas, enabling a more complete clean than flat brushes. PET bristles: Durable, lint-free material that scrubs effectively without damaging surfaces. Thickened stainless steel handle: Sturdy construction for long-term use and good leverage when scrubbing. Double-lock telescopic rods: Secure locking mechanism keeps the handle extended and prevents accidental retraction during cleaning. Function and performance Removes algae, biofilm, and dirt from glass or acrylic aquarium walls and decorations. Bristle hardness is balanced to provide effective scrubbing while avoiding scratches. Telescopic handle provides adjustable reach and comfortable grip for quick, efficient cleaning sessions. Compatibility and materials Suitable for freshwater and saltwater aquariums, glass and acrylic tanks, and a variety of tank depths and sizes. Brush head: PET bristles (lint-free). Handle: Thickened stainless steel with an inner-and-outer double-lock telescopic mechanism. Practical applications / use scenarios Routine tank maintenance: Reach the back and bottom of medium and deep tanks to remove algae buildup during weekly cleanings without moving equipment or disturbing fish. Cleaning decorations and hard-to-reach corners: Use the hemispherical head to scrub rock work, artificial plants, and tight seams where flat brushes miss. Large or tall aquariums: Extend the telescopic handle and lock it in place to clean higher glass panels or deep tanks safely from outside the aquarium. What makes it stand out Hemispherical head for comprehensive, edge-to-edge cleaning. Lint-free PET bristles for a clean finish. Robust stainless handle and secure double-lock telescoping for stability and durability. Designed to clean effectively without scratching sensitive tank surfaces. Care and use tips Rinse the brush head after each use to remove debris. Lock the telescopic rods before applying pressure to avoid accidental collapse. Replace the brush head if bristles become excessively worn to maintain cleaning performance.