Do Molly Fish Need Filter? Learn More!!

Fixing every aspect for the healthy survival of the fish is significant but not easy. Thus, to help you out, I will address one of the aquarium’s essential components, i.e., an aquarium filter, for the Mollies. So, do the Molly fish need a filter in an aquarium or not?

Yes, Molly fish do need a filter in an aquarium. A filter performs proper water circulation, aerates in the tank, and maintains beneficial bacteria. It purifies water by removing increased ammonia and nitrate, fish, leftover food, irrelevant pieces, and harmful bacteria. In addition, a filter generally keeps a neat and accurate water flow, vital for the Molly fish to thrive in an aquarium.

In this article below, we will talk about if molly fish need an aquarium filter or not, along with the advantages of having a filter in the tank. So, read till the end.

Water Parameters Needed For Shrimp

Do Molly Fish Need A Filter?

Many Molly fish owners make mistakes as they dodge the importance of proper filter installation and filtration methods in an aquarium. Unfortunately, acts like this can bring a negative impact on their survival.

Clean and fresh water is what the Molly fish require. Eliminating the fish excretes, leftover food, dead fish scraps, excess ammonia in a tank, etc., is requisite to keep their habitat tidy. For this, Molly fish need a filter in an aquarium.

Besides, contaminated water is something the Mollies avoid. Filthy water with excess ammonia and nitrite puts them at risk. Installing an aquarium filter helps get rid of such issues in a tank.

Thus, Molly fish do need a filter in an aquarium. The work performed by a filter is vital to proceed in their tank to keep them happy and prosper.

Why Does Molly Fish Need An Aquarium Filter?

While installing every necessity in a tank, getting a filter for the Molly fish is crucial too. A filter plays a vital role in keeping the Mollies wholesome in an aquarium.

Thus, here are some reasons regarding why Molly fish need a filter:

Supplementing Healthful Oxygen

Water is the source of oxygen for the Mollies. But here, the Molly fish makes a lot of waste, including their excretion, which gets mixed in the water. As a result, it makes the oxygen level impure in the tank.

An aquarium filter sweeps of Molly’s excreta and supplies clean water to them. As the water gets pure and hygienic, there will be a healthful oxygen supplement for them.

The more the water in a tank is clean, the more likely to supplement healthful oxygen to the Molly fish.

Eliminating Physical Debris

An aquarium filter eliminates the physical or solid debris existing in the tank. It swipes it off as it functions in the aquarium.

Physical debris includes a dead or rotten aquatic body, leftover food, broken pieces, etc. Such elements decrease the water quality and hamper the existing Molly fish and other aquatic beings. And of course, remember molly fish love for water current that your filter can provide.

Chemical Filtration

When it comes to chemical filtration, the Nitrogen Cycle process exists. The Nitrogen Cycle converts the toxic ammonia to a necessary composite known as nitrate. The composed nitrate is non-toxic and essential in the aquarium.

Besides, the tap water in the tank contains various harmful substances and minerals, which can harm the Molly fish. Such harmful substances and metals damage the fish’s gills and eventually cause illness because they end up breathing in toxic water. Thus, the tap water quality in the water tank is not appropriate if the Molly fish breathe the toxic air.

The Molly fish need an aquarium filter to avoid or treat such issues. A filter treats the water and keeps the water quality optimum. Make sure you choose a filter that has an option for chemical filtration to regulate the chemical levels in the aquarium.

Reduces Bacteria Buildup

Bacteria buildup is another general issue in an aquarium.

There exist some algae and bacteria beneficial for the tank habitat. Yet, their extra buildup becomes toxic for the Mollies. Increasing bacteria diminish the water quality and make them unhealthy and fatal.

Here, the filter’s biological filtration mechanism helps control the bacterial growth. The filter shelters the correct amount of bacteria to benefit the Nitrogen Cycle process. Then, it reduces the rest of the bacteria buildup to keep a proper balance in the tank water quality.

Neat And Hygienic Water

Molly fish requires a clean tank environment to live peacefully. For this, an aquarium filter installation is the best way.

A filer purifies the contaminated water and makes it neat and hygienic. Also, it keeps the water quality balanced by cleaning off every residue or debris from it.

Aquarium Nitrogen Cycle

The Nitrogen Cycle converts the excess ammonia; released from the fish through excretion to a necessary composite known as nitrate.

Here, the ammonia released is toxic for the fish. But after the aquarium beneficial bacteria performs the Nitrogen Cycle, the composed nitrate through ammonia poisoning becomes non-toxic and essential in the aquarium. Therefore, a filter neutralizes the excreta of fish to enhance their environment by this cycle.

Thus, a filter cleans the tank water and makes the tank environment better for aquatic beings by removing all the trash.

Choosing A Suitable Aquarium Filter For Molly Fish

Choosing a suitable aquarium filter for Mollies is vital to keep the tank habitat healthy. Thus, you can get an internal aquarium filter that features biological filtration for them.

While picking a filter, you must grasp that they originally inhabit slightly wider slow-flowing water regions. Due to this, they prefer slow-moving current in a tank.

The rule of thumb while selecting the correct aquarium filter states to get a filter with a flow rate of 6 times the aquarium size. For example, if you have a 10-gallon tank, managing 60 GPH (Gallons Per Hour) is significant.

For the Mollies, it is best to manage the filter flow rate of around 4times per hour. So, in a 10-gallon tank, having a 60 GPH filter flow rate, setting 40 GPH is suitable for them.

Moreover, getting a peat filter for the Mollies can be the best way to keep them secure. Such filters form soft acidic water that attracts the fish to breed in comfort.

Molly Fish Can Fit Into The Filter Opening. Do You Know?

Yes, the Molly fish can fit into the filter opening if you neglect considering the filter size and fish size accurately while getting a filter.

Filters have various features, functions, and opening volumes. Likewise, every Molly species are different in shades and sizes. So, get a filter after analyzing the size of the Mollies so that they don’t get fit inside the filter opening.

A filter opening must be half the size or at least one-third part smaller than your fish. Avoid installing a filter with a bigger size opening than the Mollies.

Correctly measuring Mollies’ size and filter opening is vital while installing an aquarium filter.

Can Molly Fish Survive Without A Filter?

Yes, the Molly fish can survive without a filter in an aquarium. However, they may lack all the facilities that an aquarium filter does in the best.

A filter provides decent water quality, cleans the water, controls the beneficial bacteria, and aerates the water for the Mollies. But in the absence of a filter, the mentioned activities may not run effectively in the aquarium.

So, you must ensure the work function of the filter held in a tank through other methods. For example, you can set adequate plants to settle the excretion of Mollies and pieces of dead fish.

Live plants help to provide healthful oxygen by eliminating toxic components from the water. Also, setting up an air pump assists to some extent in removing dead zones in the tank and supplementing oxygen to the Mollies.

However, finding a filter replacement to split the ammonia and nitrates by the beneficial bacteria is difficult. Due to this, an aquarium without a filter may get toxic for the Mollies to survive. The fish then gets sick and may eventually die.

You can use an air pump in the molly fish tank for oxygenation. Also, taking help from the bubbler might help you secure and save molly fish in the tank. Finally, your mollies love having some bubbles in the aquarium to play with.

Thus, the Molly fish can survive without an aquarium filter. But their survival may be problematic as the water quality may get degraded.

So, I suggest you get an aquarium filter for the Molly fish to make the tank water suitable. A filter is even necessary for the survival of molly fish babies; remember that.


Installing an aquarium filter can be an excellent addition for the Mollies. The work function of a filter certainly benefits them to thrive better. But that’s why the flourishing and overall life varies with or without an aquarium filter.

Thus, Molly fish need a filter in an aquarium for healthy survival. So, choosing a suitable filter without any negligence is requisite.

Keep the Molly fish wholesome by adding a suitable aquarium filter!