How to Customize your Aquarium Filter With Filter Media

How to Customize Your Aquarium Filter with Filter Media

Aquarium sizes and stock levels can vary widely so it makes sense for people to have the ability to tailor the filtration to suit their needs. You can modify most filters such as the hang-on back (HOB), cornerbox, internal, sump and canister filters by changing the type of filter media inside. The different layers of media that aquarium water passes through before it returns to the tank are called filter media. Continue reading to find out about the various types of media and the functions they perform, as well as which media you should use.

1. Mechanical Filter Media

Mechanical filtration is made up of foam pads, sponges and filter floss. These filter out any particles from the water much in the same way as a coffee filter. Mechanical media is porous so that water can still flow through it, and the size of the pores determines what size particles are caught in the material.

Use coarse sponge pads

with large pores are good for blocking most debris like fish poop and dead leaves, and when they become full of waste, you can squeeze them out in old tank water and reuse them over and over again. They don’t clog as quickly so you don’t have to clean them as often. Sponge pads are often used to replace the disposable cartridges included with aquarium kit filters.

If you still see tiny particles floating around in your aquarium, or want crystal clear water, add a filter floss or fine poly pad. This mechanical filter media has very fine porosity that can catch the tiniest bits of flotsam and jetsam in your aquarium. Because the floss pads are very dense by design, they can clog up easily and should be replaced when they turn brown in color. Both the coarse sponge pad and fine poly pad can be customized by cutting them into smaller sizes so that they fit your filter perfectly.

Fine poly pad (left) and coarse sponge pad (right) for mechanical filtration

2. Biological Filter Media

Biological filtration refers to the usage of beneficial bacteria and aquarium plants to consume the toxic nitrogen chemicals generated from fish waste, thus purifying the water. Since beneficial bacteria can grow on any surface of the tank that is well oxygenated, the filter is a prime location to increase the population. Biological media, such as

bio rings

Bio balls (or bio balls) have porous or intricately-patterned surfaces that provide “housing” to the bacteria colony. (In fact, beneficial bacteria also readily grows on the coarse sponge pads used for mechanical filtration.) The bio media is also designed to allow water to flow freely between them. This allows for more oxygen to be delivered to the bacteria. These surfaces can become covered in aquarium gunk over time. To clean them, gently wash or rinse them in old tank water until they fall off. If you’re using loose bio media, place it in a filter bag to make it easier for you to pick up.

Aquarium bio rings for biological filtration

3. Chemical Filter Media

Chemical filtration has the ability to remove pollutants and certain chemicals from the water. The most common type is activated carbon, which is a highly porous charcoal that readily absorbs medications, tannins, and other impurities. Activated carbon for aquariums usually comes in loose granules and must be contained in a filter media bag. We prefer using

Carbon-infused media pads

Because they are more manageable, they can be reduced to a specific size and offer increased mechanical filtration to remove any debris. To add chemical filtration, cut off a section of the pads and wrap it around a sponge filter. Once the charcoal pores become clogged up with pollutants, activated carbon media cannot be used again and must be replaced.

A synthetic adsorbent such as Purigen is better if you want to use chemical filtration. The polymer granules come pre-packaged in a media bag, ready to absorb organic waste and tannins. Once the adsorbent changes color from off-white to dark brown, the pores in the polymers have become saturated and must be cleaned. To clean the Purigen bag, follow the manufacturer’s instructions. Use a bleach solution to burn off organic impurities.

Certain types of filter media are made to target specific chemicals and filter them out. For example, ammonia spikes are prone to occurring when the balance of your fish tank has been disrupted, such as after moving an aquarium, experiencing a power outage, or thoroughly cleaning a fish tank. To prevent toxic levels of ammonia from building up, you can preventatively install an ammonia filter pad to absorb the ammonia and keep your fish safe.

If phosphate levels are excessively high in your aquarium, it can lead to algae growth and compromise your fish’s health. Use a phosphate pad to control the phosphate so that algae doesn’t get it. When keeping live aquarium plants, some planted tank articles recommend keeping approximately 0.5-2.0 ppm phosphate for healthy plant growth, so don’t remove too much phosphate or else you may see yellowing and browning in the leaves.

Carbon-infused, ammonia, and phosphate pads for chemical filtration

Filter Media: Commonly Asked Questions

How should I arrange the aquarium filter media?

There are many ways you can layer your filter media. Here are some suggestions. Look in the manual to find the direction the water flows through the filter. As the water enters the filter media basket, we like to use a coarse sponge pad as mechanical filtration to block the largest chunks of debris and prevent them from entering the rest of the filter media. These pads can be used as mechanical filtering if you have to use ammonia orphosphate media pad. To capture smaller particles suspended in water, you can also add the fine poly pads to your final mechanical filter layer.

Next, you can use biological filtration. Fill the media trays and media with bio media. Finally, chemical filtration can be used at the end of the filter just before water exits the aquarium. While not all products are required, we recommend that you have at least one layer in coarse mechanical filtration followed by one layer in biological filtration.

How to clean an aquarium filter without killing bacteria. Wash the filter media with old aquarium water. Coarse sponge pads are the dirtiest and can be vigorously wrung to clean it as much as possible. Bio media is beneficial bacteria. It should be gently stirred in the water, but not scrubbed. Chemical filtration needs to be replaced entirely when used up (unless you’re using Purigen, which can be cleaned with diluted bleach). It depends on the size and media of the filter as well as the amount of food that is being fed to it. As a rule of thumb, we recommend setting a calendar reminder to clean your filter every 1-3 months.

Place loose media, such as activated carbon or bio media, in a filter bag to make it easy to transport and contain.

How many years does aquarium filter media usually last? As long as it is clean enough to not impair its functionality, reusable filter media such as coarse sponge pads, bio rings and Purigen can last many, many years. If fine poly pads turn brown and water can’t pass through them, they should be disposed of. The only way to tell if chemical filtration like activated carbon, ammonia media pads, and phosphate pads are spent is to measure the water. If you have tannins or odd odors in the water and the activated carbon no longer gets rid of them, it’s time to replace it. If you are measuring ammonia or excess phosphate in the water, then the chemical media pads are likely saturated and no longer functional.

Do I need carbon in my aquarium filter? Because activated carbon (and most chemical filtration) is disposable and cannot be reused, we like to save it for specific instances when we know there are pollutants or tannins that we wish to remove. If you are preparing for an aquarium photoshoot, you may choose to use carbon to ensure the water is extremely clear. But, hobbyists tend to not use carbon on an everyday basis as it can quickly become depleted and may only see temporary results.

To take your fish tank filtration to the next level, learn how to upgrade your aquarium filter with filter media in four easy steps.