hygger HG238 Hang-on Aquarium Filter (Size M)

Important Safety Instructions

Read all instructions carefully before use.
This appliance is for indoor aquarium use only.
Ensure the power supply voltage matches the rating label on the filter.
Always unplug the filter from the power outlet before performing any maintenance, cleaning, or when not in use.
Do not operate the filter if it has a damaged cord or plug, or if it malfunctions or has been dropped or damaged in any manner.
To avoid electric shock, do not immerse the power plug or cord in water or other liquids.
Keep the filter out of reach of children.
Ensure the filter is securely attached to the aquarium before operation.
Not suitable for framed aquariums. Please check your aquarium type before installation.

Package Contents

Please verify that all components are present and undamaged upon opening the package.

Filter Unit (Main body with motor)
Inlet Pipe Assembly
Outlet Nozzle
Activated Carbon Filter Cotton
Overflow Prevention Cotton
Sponge Protection Cover for Inlet
Adjustable Hanging Hook (5-15mm)

Diagram of hygger HG238 filter components — Figure 1: Exploded view of the hygger HG238 filter components. Shows the main filter body, inlet pipe, outlet, filter media, and hanging mechanism.

Setup Guide

Assemble the Inlet Pipe: Connect the various sections of the inlet pipe and attach the sponge protection cover to the bottom.
Figure 2: Illustration of assembling the inlet pipe components.
Install Filter Media: Place the activated carbon filter cotton and overflow prevention cotton into the filter compartment. Ensure they are correctly seated.
Figure 3: Diagram showing the placement of filter media within the unit.
Attach to Aquarium: Securely hang the filter unit onto the edge of your aquarium using the adjustable hanging hook. The hook is designed for tank glass thickness between 5-15mm. Note: This filter is not compatible with aquariums that have a frame around the edge.
Figure 4: The filter unit securely attached to the aquarium rim, showing the adjustable hook.
Prime the Filter: Before plugging in, add water to the filter compartment until it is full. This will initiate the self-priming process.
Figure 5: Adding water to the filter compartment to prime it before starting.
Connect Power: Plug the filter into a suitable power outlet. The filter should start operating automatically.
Video 1: Demonstrates the setup and initial operation of a hygger aquarium filter, including connecting the power. This video shows the filter starting and circulating water.

Operating Instructions

Water Flow Adjustment

The filter features an adjustable knob on the top, allowing you to control the water flow rate up to a maximum of 400L/H. This is beneficial for aquariums with fish that prefer gentler currents, such as Medaka, Betta, or Ryukin goldfish.

Oil Film Removal Function

The filter is equipped with an oil film removal function to maintain a clear water surface, enhancing the viewing experience of your aquarium inhabitants.

Oil film removal feature in action — Figure 7: Visual representation of the oil film removal function, showing a clean water surface.

Oxygen Supply (Aeration)

The design of the filter, where water is drawn up and then falls back into the tank, also provides aeration, effectively circulating oxygen throughout the aquarium. This creates an ideal environment for fish and shrimp.

Oxygen supply and water circulation diagram — Figure 8: Diagram illustrating oxygen circulation and aeration within the aquarium.

Maintenance

Regular maintenance is crucial for optimal filter performance and water quality. Always unplug the filter before performing any maintenance.

Cleaning Filter Media

The filter utilizes multiple media types, including activated carbon filter cotton and overflow prevention cotton.
These media can be replaced individually as needed.
Rinse the filter media with old aquarium water during water changes to preserve beneficial bacteria. Avoid using tap water directly, as chlorine can harm bacteria.

Filter media for multi-stage filtration — Figure 9: Illustration of the multi-stage filtration media, including activated carbon and overflow prevention cotton.

Cleaning the Filter Unit

Periodically disassemble the filter unit to clean the impeller and internal components.
Use a soft brush to remove any accumulated debris or algae.
Ensure all parts are reassembled correctly before restarting the filter.

Troubleshooting

Problem	Possible Cause	Solution
Filter not starting/no water flow	Not plugged in Insufficient priming water Impeller jammed or dirty Air lock	Check power connection. Add more water to the filter compartment until full. Unplug, remove impeller cover, clean impeller. Gently shake the filter to release trapped air.
Reduced water flow	Clogged filter media Dirty impeller Inlet pipe obstructed	Clean or replace filter media. Clean the impeller. Check and clear any obstructions in the inlet pipe.
Excessive noise	Air trapped in filter Impeller dirty or damaged Filter not securely mounted	Gently shake the filter to release air. Clean or replace the impeller. Ensure the filter is firmly attached to the aquarium.

Specifications

Feature	Detail
Model Number	HG238-JP
Size	M
Max Flow Rate	400 L/H
Applicable Tank Volume	Approx. 20-38 L
Applicable Tank Length	Up to 50 cm
Applicable Tank Edge Thickness	5-15 mm (unframed tanks only)
Noise Level	Below 25 dB
Water Type	Freshwater and Saltwater
Features	Adjustable Water Flow, Oil Film Removal, Multi-stage Filtration, Oxygen Supply, Anti-suction Sponge Cover

Warranty and Support

For warranty information and customer support, please refer to the contact details provided with your purchase or visit the official hygger website.

Keep your purchase receipt as proof of purchase for warranty claims.

hygger HG238-JP

hygger HG238 Hang-on Aquarium Filter (Size M) - User Manual