Every fish tank filter needs a good clean once in a while. This is also true for the hang-on-back (HOB) type.
This filter just hangs on the back wall of the fish tank, and people like it because it’s simple to look after and clean.
Before we go over how to effectively clean this filter, let’s understand how it works.
How HOB Filter works?
A Hang-on-Back (HOB) filter works by using a pump to draw water up from the aquarium into a filter chamber. This filter chamber contains various types of filter media that serve different purposes.
Biological media houses beneficial bacteria that break down harmful chemicals, while mechanical media traps solid waste particles, and chemical media removes other unwanted substances from the water.
Once the water has passed through the filter media, it’s returned to the aquarium via an overflow lip.
This movement of water is facilitated either by the same pump that drew the water up, or by air bubbles that create upward water movement.
A HOB filter needs to be maintained regularly to ensure its efficiency. If the water flow rate through the filter decreases or the water level in the filter box rises due to a lack of overflowing back into the aquarium, it’s time to clean the filter.
Regular maintenance, at least once a month, is necessary to prevent buildup of decayed detritus that can lead to a rapid increase in nitrate levels. This can be harmful to your aquarium inhabitants.
Cleaning the HOB filter is a relatively quick process, taking approximately 20 minutes. Here’s how to do it.
14 Steps to Clean Hang-on-Back Aquarium Filters
- Gather all the necessary items: fresh filtration media, a small pitcher, and a bucket used only for aquarium cleaning.
- Fill the small pitcher with about 2 quarts of tank water and set it aside.
- Unplug the filter and any other electric equipment like the aquarium heater.
- Carefully remove the filter from the aquarium and place it in a clean bucket.
- If your filter has a disposable sponge or filter media insert, remove and discard it. If it’s refillable, go to the next step.
- If the sponge or filter media insert is refillable, discard the used filtration media inside it.
- Rinse the sponge or media in a small bowl filled with some of the tank water.
- Refill the cleaned insert with fresh media (carbon), close it, and set it aside.
- Clean any algae or lime deposits from the filter housing and rinse it thoroughly with fresh water.
- Rinse the newly filled sponge insert using the pitcher of tank water.
- Place the rinsed sponge insert back into the filter housing.
- Hang the cleaned filter back on the aquarium.
- Partially fill the filter with aquarium water using a small cup, and replace the cover.
- Plug in the filter and turn it on. Also, plug in the aquarium heater if it was unplugged.
Cleaning Filters: A Few Points to Remember
To maintain the efficiency and longevity of your aquarium filter, it’s important to follow these additional tips:
- If you use refillable filter inserts, ensure to seal the container of filtration media tightly. This will prevent any unwanted contaminants from entering the filter.
- Dirty filters aren’t only ineffective but can also be a breeding ground for harmful bacteria. If your filter insert can no longer be thoroughly cleaned, it’s best to replace it immediately.
- If your ‘bio bag’ filters or filter cartridges contain carbon, remember that over time, carbon loses its effectiveness. After a few weeks, it’s advisable to dump the carbon out. This not only enhances the filter’s efficiency but also improves the flow rate of water.
- Lastly, the pump on your power filter and lift tubes can accumulate dirt and debris over time. Ensure to clean them periodically using an aquarium tube cleaning kit. This will help in keeping the filter functioning optimally.
By following these additional tips, you can ensure that your aquarium stays clean and healthy for your aquatic friends.