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Chemical filtration

Many discus keepers and breeders get along just fine without any kind of chemical filtration by just performing frequent water changes. However, should you not want to go to the trouble of frequent water changes, you may opt for some sort of chemical filtration method. Sometimes it is necessary to use something such as activated carbon or resins in order to properly prepare the water for your discus.

Activated Carbon:

Activated carbon typically comes in a granular or a powder form. In essence what it does it provide a form of physico-chemical filtration. Activated carbon typically removes any phosphates, dyes, colors, discoloration, chlorine, chloramines, potassium permanganate, arsenic, chromium, hydrogen peroxide, antimony, some kinds of heavy metals and many other toxins to varying degrees. Activated carbon has also proven to be useful in removing fish medications at the end of therapy. This makes it ideal to pre-filter the water from your tap to help make it suitable for discus use, as it typically removes most of the toxins that your municipal water treatment company puts in there.

It should be noted however, that activated carbon does not remove ammonia, nitrite or nitrate, thus activated carbon alone is not a suitable substitute for biological or mechanical filtration methods.

Activated carbon can last for a few hours to a few days, depending on the concentrations of the toxins which are in the water that you are using it in.

Activated carbon is not meant to be used in biological filters, nor in mechanical filters. Many people mistakenly use it in conjunction with floss in a mechanical filter set up and leave the active carbon in there for an indefinite period of time. Once the activated carbon has run its course in removing the harmful toxins from your discus fish aquarium, it should be removed immediately, as it has served its usefulness and is not appropriate to use as part of a biological filtration method, as it is not suited to that purpose.


Resins can be compared to magnets in terms of the way they work. Resins will attract nitrates to it. There are many different varieties of resin, each with their own substance that they attract. Much like batteries, resins have a limited amount of substance that they can hold, and when they have reached that limit they need to be recharged in a brine solution. Also, just like batteries, some resins have long life spans and others have relatively short life spans.

The drawback to using resins is that while highly effective, you need to keep a constant eye on your water chemistry. There are also further maintenance steps that must be performed when using resins, and you need to adhere to a strict regimen in order to keep your discus aquarium in balance.

Fine Filters:

Diatoms and micron filters are used to catch extremely tiny particles of dirt. The material of these fine filters is so fine in fact, that even many parasites can not pass through it. This makes it an extremely attractive option for use as a filtration method for discus keepers and breeders.

As with all filters, you will want to be sure to clean out these fine filters regularly. If you do not have many discus fish residing in your discus aquarium, cleaning it out once a week should be sufficient.

Filter Flow Rate:

Filter flow rate is an important aspect to consider when setting up your filters and filtration systems in your discus aquarium. Remember that the natural habitat of the discus is in slow moving or still water, so having a filter which pumps water around your aquarium multiple times in one hour, is not going to be appropriate for your discus.

You will need to go to your aquarium supply store, and ask them for a specific filter for discus, or be prepared to fiddle with the settings on a normal aquarium filter until you can get the filter flow rate perfect for your discus.


Peat has been used by many discus fish breeders and keepers and is still highly recommended to use in your discus tank by many professionals in the field around the globe.

The peat often comes from Canada or Northern Germany, but it can usually be found in any aquarium supply store, anywhere in the world.

Peat gives off much needed tannic, fulvic, humic acids which help to reduce the pH level in your discus aquarium. Peat also acts as a natural ion exchanger which helps to reduce hardness of the water. Peat also has the unique quality of being able to bind with some heavy metals and other toxins which may be floating around in the discus aquarium water.

The active components which are active in peat, are also found in the natural black water habitats of the discus.

Another interesting quality to peat is that it will spur on sudden spawning amongst the discus population. No one can really figure out a scientific reason for this, other than maybe they like the color of the water.

If you are considering using peat as a filtration method in your discus aquarium, you will want to be sure that you purchase it through an aquarium supply store and not a garden center. You will want to ensure this because sometimes the peat that you can get at your local garden center has additives in it, which could potentially be harmful to your discus fish.

Peat is an attractive filtration method for discus keepers and breeders because it is easy to use, and is very economical.

To use peat as a filtration method in your discus aquarium you need a bag or a sock. Put one quart of peat for every twenty-five gallons of water that your discus aquarium contains, and place the bag or sock into the filter, or where you know there will be water passing through it.

You will only need to replace the peat about once every thirty days, or when you notice that the pH level in your discus aquarium is creeping up once more.

BlackWater Extract:

Blackwater extract can be found in many aquarium supply stores. Some blackwater extracts are good quality and some of them have been found to have an extremely poor quality to them, depending on the ingredients used to make it. You need to check the ingredients carefully, and try to choose a blackwater extract which is made from peat as opposed to wood.

Blackwater extracts are an excellent way of maintaining your discus aquarium clean and also making your discus feel more at home, as the blackwater extract will taint the water in the aquarium darker, mimicking the discus’ natural habitat more closely.