How to Clean an Aquarium Sponge filter:
A Simple Guide for Aussie Fish Keepers

If you’re an aquarium owner, maintaining a healthy environment is super important to keep your finned friend happy and thriving. One part of that is keeping your aquarium sponge filter clean. Don’t worry, it’s not as complicated as it sounds! In this guide, we’ll walk you through the easiest and most effective way to clean your aquarium sponge, ensuring your tank maintains the right filtration and your pet fish happy, healthy and thriving.

Why Clean Your Aquarium Sponge?

Before we dive into the how-tos, let’s quickly chat about why cleaning your aquarium sponge filter is important. These sponges work around the clock, collecting fish waste, leftover food, and other debris that can build up and affect water quality. If you’ve noticed the water getting a bit cloudy, or maybe there’s a weird smell in your tank, chances are, it’s time to clean that sponge!

The sponge also houses good beneficial bacteria that help break down waste and maintain a balanced environment, so you want to clean it to preserve those bacteria while removing the gunk.

How Often Should You Clean It?

There’s no strict rule for how often to clean your sponge – it all depends on your tank. If you have a heavily stocked aquarium, you might need to clean it every couple of weeks. In smaller, less populated tanks, once a month should be plenty. You’ll know it’s time when the sponge looks grimy or the filter’s water flow starts to slow down.

What You’ll Need

• A clean bucket (specifically for aquarium cleaning)
• Some of your tank water
• Your dirty sponge filter
• Optional and recommended: Gloves (if you don’t fancy getting your hands wet or if you have any open wounds or cuts)

Step-by-Step Guide to Cleaning Your Aquarium Sponge

Here’s how to do it without losing those helpful bacteria:

1. Remove the Sponge Carefully

Take out the sponge gently. Be mindful not to squish it too much – the bacteria are delicate, and rough handling could reduce their numbers.

2. Use Tank Water to Clean the Sponge

This step is key! Grab the bucket and fill it with water from your aquarium (never use tap water – it can kill the beneficial bacteria). Dunk the sponge in the bucket and give it a few gentle squeezes to get rid of the dirt. You’ll see the water go brown and cloudy, but don’t worry – that’s normal. 

Why tank water? Tap water contains chlorine and other chemicals that can harm the bacteria, so it’s best to stick to tank water.

3. Squeeze, Don’t Scrub

The goal here isn’t to make the sponge look brand new. You just want to remove the excess waste. Too much scrubbing will eliminate the good bacteria, which are crucial for keeping your tank balanced. A few squeezes should do the trick.

4. Reassemble and Restart the Filter

Once your sponge is reasonably clean, put it back in the filter, reassemble everything, and turn the filter back on. You might notice the water in your tank looks a little murky for a bit, but that’s totally fine – it’ll clear up soon.

5.Your health and safety is paramount

If you are not wearing gloves, wash your hands thoroughly with hand soap, making sure to scrub the surfaces between your fingers and under your nails. If you have open wounds and cuts on your hands, we recommend you wear gloves. We find the Equine gloves with a shoulder loop effective. 

If you have open wounds and cuts on your hands, we recommend you wear gloves.

What About Other Aquarium Filters?

If your setup includes more than just a sponge filter, you might be wondering how to clean those parts too. Hang-on-back filters, canister filters, and internal filters all need a bit of TLC from time to time. While we’re focusing on sponge filters here, the cleaning method is pretty similar for most of them – just be gentle, avoid tap water, and clean the components in stages to maintain the biological balance.

Common Mistakes to Avoid

We all make mistakes, especially when we’re new to fishkeeping. Here are some things to avoid when cleaning your sponge filter:

Using tap water:

As mentioned earlier, tap water contains chemicals like chlorine, which can wipe out your beneficial bacteria. Use your aquarium water. 

Over-cleaning:

If you scrub too much, you risk removing too much bacteria. This could cause your tank to undergo another mini-cycle or, worse, a tank crash, which can harm your fish. Remember to clean less so you don’t remove the good beneficial bacteria that help break down food, fish waste and dead plant materials and turn them to a relatively safe nitrate.

Not cleaning often enough:

Letting the sponge get too dirty can cause poor water quality, stressing your fish.

FAQ Section

Here are some quick answers to questions you might have about cleaning your aquarium sponge:

Q: How long will my sponge filter last? 

A: With proper care, your sponge filter can last for years. However, if you notice it falling apart or losing shape, it’s time to replace it.

Q: Can I clean the sponge with soap? 

A: Absolutely not! Soap can leave a residue that’s harmful to your fish. Stick to tank water, and your sponge will be just fine.

Q: My filter isn’t working as well as before. What should I do? 

A: It could be a sign that the sponge is clogged. Try cleaning it, and if that doesn’t help, check for any blockages in the filter system itself.

Pro Tips for Maintaining Your Sponge Filter

Rotate Cleaning:

If you’re running multiple sponge filters, clean them at different times so you don’t disturb the entire beneficial bacteria population at once.

Keep an Eye on Flow:

Reduced water flow is a sign your sponge needs cleaning. If you notice your filter isn’t pushing as much water as it used to, it’s time for a clean.

Inspect for Wear:

Every time you clean the sponge, check for any signs of wear and tear. A sponge that’s falling apart can affect filtration.

Wrapping Up

Cleaning an aquarium sponge might seem like a small task, but it plays a huge role in keeping your tank healthy. With a little routine care, your sponge filter will last a long time, and your fish will thrive in clean, balanced water. Just remember: no soap, no tap water, and don’t overdo it!

Happy tank cleaning!

Do you have any other fishkeeping tips or cleaning tricks? Share them in the comments below!