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How to Get Rid of Fish Tank Smell

how to get rid of fish tank smell

I am very sure that a lot of store owners can relate when it comes to a smelly aquarium. There will come a moment that your tank will have a horrible smell for a lot of reasons. Normally, if your fish tank has no issues, it should be odor-free. But if you begin to smell a stinky odor in the tank and its surroundings, then some problems need to be solved immediately.

But how to get rid of fish tank smell? Occasionally, you may find your fish tank produces a very bad smell. It is so bad that anyone can locate your fish tank using only their nose. If he happens, the initial thing to do is to know what is the cause of the smell. After that, try to find a simple solution to get rid of the smell. Fortunately, all of the information you need related to this topic will be in this article.


Why Does my Fish Tank Smell Bad

If you are good at maintaining your aquarium, it will not likely produce a very bad odor. Usually, the foul odors are coming from the decomposing waste inside the aquarium must be remove or clean. Fish foods that are uneaten will rot underwater along with the excessive amount of fish waste which causes the water to smell bad. There are also other materials that cause the smell so bad. Why Does my Fish Tank Smell like Rotten Eggs, please check some of them below:

Too Much Excess Foods

When you overfeed the fish, the tendency is it will have a lot of leftover foods that become uneaten and will just rot in the bottom of the aquarium. What happens with these uneaten foods is they will help in promoting the growth of bacteria where it can release gases with a terrible odor.

Decomposing plants

If you fail to clean a decomposing plant in the aquarium, it also has the tendency to produce a very bad smell. Although, this reason will not quickly happen because dead plants are easy to locate and remove in the tank. But if you fail to remove it immediately, it can affect the quality of the water and produce a not very pleasant smell.

Rotting Dead Fish

If a fish of the aquarium dies and you fail to remove it immediately, I am pretty sure that your tank will be smelly quickly. Dead fish which is hidden in some aquarium decorations cannot be easily spotted and if it remains untouched for a few days, then expect the water to get smelly. The fish’s proteins and oils will float, creating a very foul odor.

Overcrowded Aquarium

When there are too many fish in your aquarium, it can also result in producing a very bad smell. The fish waste produced by the vast number of fish may be too much for the filters and the good bacteria to handle, resulting in a very foul odor.

How to Keep a Fish Tank from Smelling

why does my fish tank smell bad

There are some ways that you can do to prevent or at least control the aquarium from being smelly. Please check on how to do it below:

Air Quality

If you own multiple tanks or a large fish tank, the first thing to look at is the air humidity. You will need to focus on the air quality of the room in which your aquarium is located. Meaning, if the air quality of your room is good, that can cause a scent. You can use a dehumidifier to help maintain the quality of the air.

Always Take a Look

You need to be constantly observing on what is happening in your aquarium. Take a look behind the fish tank, on the side, underneath the stand, or in the water, and check for anything that needs to be removed immediately. You can also take the floor and the aquarium stand and make sure that everything is dry. Leaving some parts around the tank wet all the time can produce molds that create a smell right around the fish tank.

Excellent Fish Tank Maintenance

If you’re doing your best when it comes to the maintenance of your aquarium, then it will be a lesser chance of getting smelly. When it is needed to change the water, then do it immediately to prevent further complications in the future. Anything that requires immediate action, like nitrates buildup, algae bloom, and others, needs immediate action. Of course, if you have a proper maintenance schedule, then that will not be a problem.

Filtration System

You also need to check your filtration system consistently to prevent any development of foul odor. For example, you can check on your back filter, and if you have not changed your filter pads in a while, that can create a lot of gunk buildup, which produces a bad smell. My advice is to change those pads when they get gunky or nasty to prevent the bad smell from formulating and also helps the aquarium to look good.

Fish Food Gets on the Rim of the Fish Tank

One of the most significant contributors to a smelly fish tank is when the fish food gets on the rim of the fish tank. And combined with the water splashes coming from the aquarium, then you have a mixture of food and water, which can get nasty. It might not be the water that is smelling but the rim of the tank full of dirt. What you do is clean it using a clean cloth to wipe the food remnants off.


There will be a day that your fish tank smells so bad so learning how to get rid of fish tank smell is an excellent skill to learn as an aquarist. Many reasons can cause a foul smell in the water of the aquarium and its surroundings. The most important thing to do is to know the cause of the smell and what needs to be done to eliminate the foul odor. If you constantly clean and follow a strict maintenance schedule, then it is not likely that your aquarium will emit a bad smell.

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