Do Fish Really Need a Filter?

Fish tank

A filter has been recommended as a very important tool for fish over the years. It comes in handy to aid biological filtration for your fish. So, to aid good biological filtration processes in your tank, your might want to consider a filter for your fish. However, some people have felt that fish don’t really need filters.

In this article, therefore, we will be aiming to clear the air as we will consider whether or not a filter could be necessary for your fish.

Do Fish Really Need a Filter?

Having a filter is not something necessary to keep a healthy fish tank. However, you need biological filtration to run a proper healthy fish tank. Biological filtration helps to make water safe for your fish which means it aids the cycling of water in the tank.

Biological filtration helps to break down waste such as ammonia, then convert it to nitrites and eventually, break it down to nitrates. So, if you can successfully provide an adequate amount of biological filtration without the use of a filter, then, your fish might not need a filter.

However, without the aid of filters, you might be limited in the number of fishes that your tank will be able to culture as not all fishes can survive without filters.

What Is The Function of a Filter?

A filter can serve double functions for your fish. It aids in water movement or circulation as we have rightly discussed. It also helps in removing both soluble and insoluble dirt from water.

This process of cleaning water using a filter is called the nitrogen cycle especially when you refer to the biological filtration processes. Even though there is a chance that you can work around not using filters, you will need something else to help you perform these functions.

You can work around water movement for your fish by making use of an air pump. However, for the nitrogen cycle, things could get a little complicated. You will need a thick substrate and many live plants to be able to create a system around it.

First off, you have to identify the source of dirt in your fish tank. It could be in the form of rotting food leftover, decomposing plants, or fish waste. You will need a mechanical filter for your fish to get rid of this dirt.

The mechanical filter works in a way that you push water through some form of filter media that could serve as a strainer. This will help catch floating particles using a sponge, gravel media, or filter floss. This does not end the dirt ruckus though.

Apart from the particulate dirt, fish waste and decaying organic matter still give out some toxic chemicals that you have to filter out. If you don’t filter out these toxic materials, they could kill your fish easily and quickly.

This is where a biological filter will come in place. A biological filter involves microorganisms and bacteria and it converts waste toxins of fish into substances that are not toxic. Since most of the fish waste is composed of ammonia, this filter will convert toxic substances into nitrates that are not harmless to the fish.

Chemical filters should help you deal with other toxins that could be present in your tank. It works with carbon or other chemical resins to help extract these toxic elements.

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Can a Filter Help Oxygenate a Fish Tank?

Just as humans need air to survive, fish also need air. This means that your fish tank needs to be adequately aerated especially if your fish cannot take the air by itself from the water surface. Some persons opt for air pumps, although this could require more space.

If you have a small fish tank, you can easily work with a filter as your prime aeration kit. You will have to consider going for a filter that is effective at adding oxygen to water as it flows through it. Usually, once the flow rate and the pressure of the water is high, the rate of aeration will also be high.

A simple Hang-on back filter will help you successfully aerate your fish and it comes with an output that drops water into the surface of your fish tank. This will also aid surface agitation in your fish tank. In addition, this filter will help to circulate the water in the tank.

The filter will ensure that water moves cyclically so that the content at the bottom can move up top. The content at the top will be in contact with the atmosphere so it will come with a better concentration of oxygen.

If you have a big tank and a filter would not be sufficient, you can work with a combination of a filter and an air pump. If you can get a well-designed combo, you would not need to use your filter as a primary means of oxygenation.

What Could Happen If Your Fish Tank Don’t Have a Filter?

Not having a filter is not particularly uncommon. A plant-only aquarium or a properly planted tank with a few fish can function without a filter. For simple fish tanks too, you can remove the fish from time to time, clean the tank, replace the water, and put the fish back.

However, even with all these alternatives, there is no denying that filters could make life easier for you and your fish. These filters could also be the reason why your fish could remain alive if you have them installed. So, if you have a basic fish tank, the best practice will be to get a filter.

If you are happy keeping a few fish in your tank with plenty of plants, there are some species of fish that could survive. However, for this to work, the plants have to be dense and robust. You must also ensure that water is being circulated constantly. Air stones will also come in handy in such a setup.

For this setup too, you must also be willing to make water changes from time to time. This will require a lot of water per time. If you forget to change the water at any point, you could risk losing some of your fish.

For a small or an average tank, you will only be able to work with five or six small fishes without a filter. You will also have to ensure that you change the water regularly.

You must bear in mind that different fish produce different kinds of waste and as such, you will have to adjust the kind of filtration based on the species of fish. So, if you are considering a filter-less tank, you have to make an ideal choice for the species of fish.

Some fishes could also do well without filters. Shrimp, betta, cory fish, harlequin rasboras, and Goldfish among many others are some of the fishes that could work without filters.

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Different species of fish have differing water needs, so not all fish might need filters. Bettas and goldfish are some of the fishes that could do well without the use of filters.

As we have learned, however, to give your fish a better chance at long life, a filter should not be something to compromise on. So, look through our content and you will find some insightful tips about why filters are necessary.

Enjoy your read.

Written by Justin Michaels

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