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Can You Turn a Fish Tank Filter Off at Night?

Can You Turn a Fish Tank Filter Off at Night?

Let’s face it – you can’t keep up with the noise your fish tank is producing. It denies you from your sweet sleep. Also, the high-power fish tanks tend to throw the electric bill over the roofs every month.

The idea of switching off the filter at night may seem like the only way to stop your miseries. At least you can have a good sleep, and you will cut the extra costs.

But wait! Is it the right way to successfully wade through this issue?

Well, the answer to this question is rather delicate and not like a yes or no thing. If you can, some earplugs might be of little help, but it won’t be effective. Alternatively, maybe you can buy another filter. But all make noise, and you’d have to go deeper into the market and your pockets to get one that’s a bit bearable.

The bottom line is that your fish needs a filter as it’s the heart of the fish tank. Without it, they can’t survive. To arrive at something, you must put some factors in place and the effects they will have on the aquatic life.

So before we skin this cat, it’ll be right that we begin from a common ground. Why do you need a fish filter in the first place?

Is a Fish filter necessary?

Don’t be carried away with this notion that without a filter, you won’t have healthy fish. A filter does the biological control part while fish health is dependent on various factors.

When we talk about biological control, we are talking about the factors that make the tank safe for fish inhabitation. We’ll go into the details in a minute.

If you have other methods you can employ to achieve the best biological filtration; they’ll be no need for a filter. The methods must work, though to avoid murdering your fish.

There is one downside of not using a filter. The number of fish you want to keep may limit you. Remember, the oxygen concentration is low. The fish will be competing, and there’s a high chance that only a few will make it.

If you’ve decided to use a filter, then that’s great. Here are the reasons why you shouldn’t sideline a filter.

  • Bacterial Growth

If you never knew, a filter is not only about keeping your water clean but the successful growth of the bacteria that determines the health of the fish.

A filter creates a conducive environment for their growth. Their work is to convert the toxic substances like nitrite and ammonia into nitrate.

The bacteria take close to a month to grow before they can take over the tank. The many they are, the safer the tank. If you deny the bacterial Oxygen, they won’t last twenty minutes which endanger the fish.

  • Cleaning of Water

The leading cause of death of the fish is not because they lacked enough Oxygen. The culprits behind the dying are the debris and toxins like nitrates and ammonia. The work of the filter is to prevent the toxins from taking dominance on the fish tank.

  • Providing Enough Oxygen

Your fish don’t just need Oxygen, but clean Oxygen. It’s what gives the strength to swim around and be healthy. With clean Oxygen, there is fresh agitation which benefits the fish a great deal.

One last thing – some fish can survive without a filter. You are probably shocked. Yes, fish species like goldfish, blind cave tetras, zebra Danios, and wild-type guppies can surprisingly do well without a filter.

But still, every fish will perform better with excellent biological filtration. The purpose of this is to oxygenate the water to keep them alive.

Now, there are two kinds of fish tank pumps that determine the usage of a filter. With the right one, you can judge if you should use a filter at night or not.

Pumps Connected with the Filter

Records have it that many people choose these to be their go-to tanks. At least, they are not expensive and are versatile enough to accommodate different types of fish and aquatic plants. Also, maintaining them is not an uphill battle.

For such a tank, debating whether to turn off the tank or not is not a matter of discussion. The tank entirely relies on the filter to function. Even if the tank has enough Oxygen, this should not be a reason to switch off the filter.

The air cables running from the power source, the filter, and air pump is the same. Once the interconnection is interfered with in any section, it affects the fish and aquatic plants.

Your fish can’t survive 8 hours long with unfiltered water. Remember, the issue here is not the Oxygen but the toxins.

Air Pumps Separated from Filter

As the name hints, there is no direct connection with filters on such a tank. However, this doesn’t mean that you can switch off the filter for the better part of the night. Eight hours is still long. You’ll have to wake up in the middle of the night to switch it back on.

First of all, the air pump should be right, and I mean GOOD. Also, it must be separated from the aquarium filtration unit to fall into the category.

Don’t switch off the air pump before you are sure that the filtration units work perfectly. The output per hour should support the number of fish and aquatic plants on the tank.

Correlation Between a Air Pump and Filter

The two works hand in hand. The air pump cannot provide air directly to fish without being filtered. On the other hand, a fish pump will have no use if the filter is missing.

When it comes to shutting the fish pump, it’s a different case. Yes, you can shut them down, but it will depend on some factors.

Size and Number of Fish

Here, we are talking about oxygen concentration. What matters is the rate at which fish is using it. Not to forget that the aquatic plants also use Oxygen at night.

When you have more fish, it simply means that you have more gills to feed with Oxygen. On the other hand, the bigger the fish, the more Oxygen they will need. Also, the many aquatic plants, the more Oxygen they’ll have to take back at night.

If your tank is full of large and numerous fish, the idea of shutting the fish tank should not even cross your mind.

The Filtration Unit and Size

The filtration unit matters a great deal if you should shut the air pump. Point to note, the type of filter you use is what will determine your action.

Some filters, for instance, submerged filters do not produce enough Oxygen that can sustain a high number of fish. They are only comfortable with two to five fish in the tank.

A hang-on filter produces the amount of Oxygen that can fit the high number of fish. Such filters work by giving back more Oxygen to the tank when releasing back clean water into the container. If your pump is separate from the filter, switching off the pump at night is a go.

Temperature of Water

Cold water can hold more water than hot water. So the warmer the water, the less Oxygen will be dissolved into the water.

If your tank is full of large fish, you use submerged filters, and the water tends to be warmer, then your fish are at a higher risk.

On the other hand, if you can find a way of making the water cooler with limited fish, you can confidently close your tank at night without taking into account the adverse effects.

Now, you will quickly notice a danger when you close the water filters. One of them is lacking enough Oxygen.

For instance, if you notice your fish at the surface gasping for air; quickly turn on the water filter. Some other characteristics of low Oxygen include;

  • The fish may be having trouble breathing with gills which they’ll be flaring; this should be a red light that Oxygen is lacking in the water.
  • The color of the gills may not be the same as the color of the body. The discolorations show that the gills don’t have the right amount of Oxygen like the body.

To get the level of oxygen concentration, a meter reader will help a great deal, and you will know the measures to take.

The Takeaway

You may have different reasons as to why you decided to put an aquarium at your house. Maybe you wanted to have the beauty of the inner oceans right at the center of your room. Or you were fascinated by the life of these swimming creatures.

All in all, you must have had concrete reasons to keep a fish tank. So don’t let the other side of the coin purge take the better of what you get from the fish.

Written by Fabian

Hey, I'm Fabian, chief editor at Aquarium Nexus. I really enjoy the aquarium hobby and love sharing my experience with others. If you have any questions feel free to contact me or leave a comment below.

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