Does a Fish Tank Act as a Humidifier

Does a Fish Tank Act as a Humidifier?

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Anything that emits steam, moisture or water into the air can be a humidifier in your home. Placing a dish of water on/in front of your heater, boiling water on the stove, hot water from the faucet and opening your dishwasher can all put humidity into a dry room.

But, what about a fish tank being able to act as a humidifier? A fish tank can act as a humidifier but it depends on where you’re attempting to increase humidity and what for. While this can be a very handy way to keep a dry room stable, it’s not always going to be the best idea.

Regardless, if you do things right, it’s a great alternative to an actual humidifier or any of the other suggestions mentioned above. But, this will require a bit of resourcefulness, being savvy and applying a little common sense.

How Do You Increase a Room’s Humidity with a Fish Tank?

The typical humidity range in any given home should be between 40% and 55%. Using a fish tank to increase humidity that sits below this standard can be a perfect solution. This is because the heated water of the tank must release its energy to maintain its temperature and release of gasses.

Measure the Air’s Humidity Levels

This means that it keeps the air and surrounding area nice and humid in natural way. So, in order to do this effectively, you should use a hygrometer in your home to check the room’s general humidity levels. Then, determine what room you want to use it in and how big your tank is.

Determining Room ; Tank Size

Medium and small tanks are good for living rooms, offices and hallways. Bigger tanks are excellent for basements, climate-controlled attics or other wide-open spaces without a lot of human traffic. But, if you have a palatial living room, then a large fish tank should do nicely.

Then there’s the matter of placement. In order for the humidity factor to be effective from the tank, it must rest in the right spot. It should not only be beneficial for the fish but it must also disperse the moisture in the appropriate direction. It does no good to put it in front of a window with most of the airflow going in that direction.

An ideal place would be on a wall that receives projected indirect sunlight from an adjacent wall or window. Don’t put a fish tank in front of the entry/exit way as the shifts in temperature will stress out your fish. Likewise, an increase in a room’s temperature can negatively affect the fish, especially if they are particular about it.

Maximizing the Use of a Room’s Airflow

However, you want to understand how air flows in the room and make sure the tank sits in a place that will satisfy that current. While you can use a fan, it should only push the air around the room, it shouldn’t change the temperature of the tank or the room. A small desk-size oscillating fan should be fine.

Pay attention to weak areas in the windows and doors to see if air is leaking into the room. Then evaluate where vents are and how the wind blows against the house in relationship to the fish tank. It may be useful to lick your finger and hold it up into the air. Pay attention to how the air feels against it.

When Shouldn’t You Use a Fish Tank to Increase Humidity?

While a fish tank can be invaluable in keeping a room comfy and humid, it’s not advisable to put it in the bedroom, kitchen or bathroom. This is because fish tanks are notorious for releasing noxious gasses like ammonia that can cause severe health issues and respiratory problems.

The only caveat is the bathroom, however. If you have a large bathroom with plenty of space and ventilation, then it should be okay to have it there. Otherwise, the bathroom or kitchen, are by their nature, humidifying mechanisms for your home and a fish tank may over-humidify the space. When an abundance of humidity is present, it can create moldy conditions.

Also, if your room is at a perfect range, then there’s no need to use a fish tank to keep it moist. In fact, you may even need to decrease humidity to ensure everything stays healthy.

How Do You Decrease Humidity from a Fish Tank?

If your fish tank pushes a room’s humidity beyond 55%, then you will have to contain the humidity. If this gets out of control, mold can grow inside and outside of the tank. It will attach to wood, paint, drywall and other similar materials. Mold, especially black mold, is very dangerous to pets and people alike.

The greatest tell tale sign that your room is more humid than it should be is if windows, mirrors and other glass shows condensation. However, use a meter to make sure. Then, you will have to contain the evaporation with some kind of cover.

Covering the Tank

You can use Plexiglass, a plastic sheet or some other form of mold-resistant material over the top of the tank where the air escapes. When you do this, however, you have to ensure heat and moisture won’t increase within the tank itself. You will have to create a delicate balance that satisfies the room and your fish.

Avoid wood, plywood, cardboard or other natural, porous material. These things will absorb the moisture and develop mold, which will emit into the surrounding environment and the tank. If you do use these things, you will have to change them out the minute you notice discoloration.

Using a Dehumidifier

Then you’ll want to use a dehumidifier and/or open some windows to let out the excess moisture. It is not a good idea to turn on more heat or a fan as these will simply push the water molecules around. Doors, windows and other openings should offer ways to let air escape.


How Do You Know the Tank is Working to Humidify the Room?

Every week, you should notice about a two inch difference from the top of the tank. This is how you know it’s humidifying the room it rests in. But, it’s not enough to see water missing from the tank, you should use a meter to measure the air to make sure.

How Do You Know the Fish Tank Will Be Enough to Humidify a Room?

Unfortunately, you won’t know off hand if the tank will be enough to humidify a room. In extreme cases, you may have to use both a humidifier and a fish tank to get the job done. This is also true if you can’t place your fish tank in a spot that maximizes airflow in the room.

Does Anything Else in a Room Affect the Rate of Fish Tank Evaporation?

The rate at which your fish tank evaporates will determine how much humidity it emits into the room. While there will be a natural release rate, there are other things that can affect it. Summertime temperatures, heaters in winter and fans can all increase a tank’s evaporation.