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. Most filters – such as hang-on-back (HOB), corner box, internal, canister, and sump filters – can be modified by changing the types of filter media used inside. Filter media refers to the different layers of materials that tank water gets filtered through before returning to the aquarium. 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 uses sponges, foam pads and filter floss to physically remove any debris from the water. It is similar to a coffee filter. Because it is porous, water can still flow though it. The size of pores determines the size particles that are trapped in the media.
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. Also, they don’t clog up as quickly, so you don’t have to constantly clean them. To replace disposable filter cartridges in aquarium kits, we often use sponge pads.
You can add a fine Poly pad to your aquarium to remove any tiny particles. 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
Bio balls and bio sponges have many porous or intricately pattern surfaces to provide housing for bacteria colonies. The coarse sponge pads used to mechanically filter water are also a good place for beneficial bacteria to grow. 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. Aquarium gunk can build up on these surfaces so you should clean it every 1-3 months. You can gently rub the surface with old tank water or waving it until any debris is gone. (If you are using loose bio media that does not come in a bag, put it in a filter media bag to make it easier to pick up and clean.)
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 popular is activated charcoal, which is a porous carbon that easily absorbs medications, tannins, as well as other impurities. Activated Carbon for Aquariums is typically supplied loose granules that must be placed in a filter bag. We prefer using
carbon-infused media pads
because they are easier to handle, can be cut down to a custom size, and provide increased mechanical filtration for straining debris from the water. For added chemical filtration, you can cut a portion of the pad and wrap it around a sponge filter using a zip tie or rubber band. The activated carbon media must be replaced once the pores have become clogged with pollutants.
A synthetic adsorbent such as Purigen is better if you want to use chemical filtration. The pre-packaged polymer granules are ready to absorb organic and chemical waste. The adsorbent’s color changes from white to dark brown and the pores 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. To keep the phosphate levels under control, you can use a phosphate media pad. This will prevent algae from taking advantage of it. Some articles on aquariums recommend that you keep a phosphate level of 0.5 to 2.0 ppm for healthy growth. Otherwise, the leaves may yellow and become brown.
Phosphate, ammonia and carbon-infused pads for chemical filtration
Frequent Asked Questions about Filter Media
How should I arrange the aquarium filter media?
There are many ways to layer the filter media in your filter, so these are our general suggestions. The first step is to look in the manual and find out which 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. If you need to use the ammonia or phosphate media pads, you can place them here since the pads also serve as mechanical filtration. You can add the fine poly pad as an additional layer of mechanical filtration to capture even smaller particles in the water.
The biological layer is next. So fill your media trays with biomedia. You can also use chemical filtration such as activated carbon and Purigen to filter the water before it leaves the filter. 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. You can use the coarse sponge pads to clean it. Bio media houses beneficial bacteria and should be gently agitated (not scrubbed) in the water. Except for Purigen which can be washed with bleach, chemical filtration must be completely replaced. 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 (like activated carbon and bio media) in a filter media bag to make it easier to contain and move around.
How long does aquarium filter media last? Reusable filter media – such as the coarse sponge pad, bio rings, and Purigen – can last for many years, as long as it can be cleaned sufficiently so that its functionality is not impaired. Fine poly pads should be disposed when they turn brown in color and water cannot move through them as easily. You can only measure the water to determine if any chemical filtration such as activated carbon, ammonia pads, or phosphate pads has been used. It’s time for you to replace activated carbon if there are tannins or other unpleasant odors present in your water. 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 require carbon in my aquarium filtration? Activated carbon, like most chemical filtering, is disposable and cannot re-used. However we keep it for special occasions when we are aware of any tannins or pollutants that we need to remove. You may use carbon to make sure the water is clear when you are getting ready for an aquarium shoot. Most hobbyists don’t use carbon every day because it is quickly depleted and can cause temporary results.
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