BEVINKATE Aquarium Filter Baffle, Large 4.6-Inch Extendable Flow Controller

BEVINKATE Aquarium Filter Baffle softens strong hang-on-back filter outflow for a calmer aquarium, with an extendable design and a removable built-in sponge filter.

• Diffuses strong HOB-filter outflow — reduces turbulence, splashing, and noise.
• Fits outlets up to 4.6 inches (11.68 cm) wide — provides wider coverage for larger outputs.
• Triangular suction-cup mount — attaches to the glass without tools.
• PETG construction with 3D-printed parts — made for long-term use.
• Removable sponge filter — captures some debris and can be rinsed.

Fast-moving water from a filter outlet can make it harder to maintain a calm, low-flow area in a tank. This baffle is designed to disperse the outgoing current into a gentler, steadier surface for bettas, shrimp, small fish, long-finned species, and plants that prefer less flow. Its extendable layout lets you adjust the baffle’s position for different flow strengths.

How does the BEVINKATE baffle change filter flow?

The panel diffuses water coming from a hang-on-back (HOB) filter, helping reduce turbulence, splashing, and the noise associated with strong outflow. By softening the current, it helps prevent small fish, long-fin species, shrimp, and floating plants from being pushed around or stressed by rapid flow.

• Creates a gentler, steadier water surface.
• Position adjusts to suit different flow strengths.

Will it fit my hang-on-back filter outlet?

This larger-size baffle fits HOB filter outlets up to 4.6 inches (11.68 cm) wide and is intended for larger outputs in medium to large aquariums. For an outlet under 3.8 inches (9.65 cm), the smaller size is recommended for a better fit.

• Designed to cover wider filter outputs.
• Has a low-profile look inside the tank.

How do I attach and clean the baffle?

Line up the baffle with the filter outlet, press its suction cups onto the glass, and position it to meet the flow. The triangular suction-cup layout holds it against the tank wall, and installation requires no tools. Both the panel and built-in sponge filter can be removed for rinsing.

• Rinse with warm water before first use.
• Rinse during regular maintenance to keep the parts clean and functioning effectively.

BEVINKATE Aquarium Filter Baffle suits aquarium keepers looking to soften a larger HOB filter’s outflow for fish, shrimp, or plants that prefer a low-flow environment. Its adjustable position, glass-mounted suction cups, and removable rinsable components make it a practical choice for managing strong outlet flow in medium to large tanks.

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