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How To Oxygenate A Fish Tank Without A Pump

how to oxygenate a fish tank without a pump

Your pet fish, just like most organisms, needs oxygen to breathe and live. In their natural habitat, the oxygen provided by the water, in the absence of pollution, is enough for them to breathe. In an aquarium, however, you usually need a pump to ensure a steady supply of oxygen for your pet fish.

There are times, however, that a pump may be unavailable. In that case, can you still ensure a steady supply of oxygen for your pet fish? Fortunately, there are ways as to how to oxygenate a fish tank without a pump.

But first, there are things to consider. The proper temperature must be maintained for the fish tank, for an increase in temperature facilitates evaporation of air molecules, including oxygen. Having a high temperature means that you have to track the oxygen levels in your fish tank to make sure that there is always an adequate supply.

You must also know when your fish tank is having a low oxygen supply and needs to be oxygenated. Some signs include reduced activity by your pet fish, reduced movement and eating less, and difficulty breathing. If you notice these signs, you need to oxygenate your fish tank as soon as possible.


Methods to Oxygenate a Fish Tank without a Pump

Pour some water

One of the easiest ways to oxygenate a fish tank is to pour some water into the aquarium. Water itself contains molecules of oxygen that your pet fish needs to breathe. Pouring some water increases molecular activity in the fish tank. More than that, by pouring some water, you are pushing some oxygen molecules from the air, into the water, increasing its volume for your fish.

How do you do it? Just take a large cup and scoop some water from the fish tank. Put it above the fish tank, and at a certain height or level, pour it into the fish tank.

The amount of oxygen being pushed into the aquarium from the air depends on how high you pour the water. The higher, the better. Pouring water into the fish tank at a certain height also increases water molecule activity in the fish tank. It allows oxygen molecules trapped below the fish tank to rise in the fish tank for the eventual use of your pet fish.

How often do you need to do it? Low activity from your fish is a sign that there is a low oxygen level in your fish tank, so it’s time to increase the oxygen levels. If after doing it, your fish started moving towards the surface, it means that there is indeed a high concentration of oxygen near the surface. Keep on doing it until your pet fish start moving and acting normally.

Change the water in the fish tank

Sometimes though, pouring water may never be enough, especially if there is a really low concentration of oxygen throughout the fish tank. In this case, you need to change the water in the fish tank. The water from the fish tank is probably saturated by carbon dioxide and other molecules. New water means a new, fresh supply of oxygen for your pet fish.

How much do you need when replacing water from the fish tank? Replacing more or less fifty percent of the water from your fish tank is just about right. It can ensure a steady supply of oxygen in your fish tank for quite some time.

Try to use some ice cubes

use some ice cubes

At times, and due to weather, the temperature may rise. These may result in reduced oxygen levels in your fish tank. You can use some ice cubes to cool down the temperature in the fish tank, restore it to proper levels, and prevent the reduction of oxygen supply in the fish tank.

To do it, put some ice cubes in a closed bag, then put them into the aquarium for quite some time.

Put some plants

Some plants can live underwater. Those plants, however, still perform the basic function of absorbing carbon dioxide and releasing oxygen, through the air or water. Having some plants in the fish tank may is good for oxygen supply, as well as maintaining the balance of the ecosystem in your fish tank.

Use filters

Using filters is also a good way to oxygenate a fish tank without a pump. By circulating water through your fish tank, it picks up oxygen along the way. The oxygen molecules can be added to the overall supply of oxygen in your fish tank. Water falling in a filter also increases the chances of it getting added oxygen molecules that eventually be put into a fish tank for your pet.

Water dripping from the filter will also create some molecule movement at the surface. This will allow releasing of oxygen molecules that can be consumed by your pet fish. Movement at the surface will also allow water to make contact with air and the atmosphere, allowing the absorption of oxygen.

Just make sure that your filters are always clean. A good, clean filter ensures the smooth flowing of water. This will allow your fish tank to gather more oxygen molecules along the way, all for consumption of your pet fish.

Put some ornaments

There are some ornaments and artificial objects, like stones, that can help for better aeration in the fish tank. Better aeration will allow for the release of trapped oxygen molecules as well as better distribution of oxygen in the fish tank.

Better distribution and dispersion of oxygen in the water will ensure a good and adequate supply of oxygen for your pet fish. It will minimize the “dead spots” in the fish tank. ‘Dead spots” are places in the fish tank that has little or no oxygen supply.


Though pumps are great and very helpful, there are various ways as to how to oxygenate a fish tank without a pump. You can use these ways and methods to make sure that your pet fish gets a steady supply of oxygen.

The methods are proven to be effective and can always be used and applied immediately. It will allow you to pursue your passion for fish keeping without spending that much.

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