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How Many Guppies in a 20 Gallon Tank?

How Many Guppies in a 20 Gallon Tank?

Guppies are a favorite of most hobbyists thanks to their colorfulness, ease of care, and the ability to adapt to a variety of water conditions. And if you are wondering if it’s ideal to keep them in a 20-gallon tank, then this article will take away the doubt.

How many guppies in a 20-gallon tank? Well, at least 14 guppies will thrive in a 20-gallon tank. This is because plants, decorations, and the substrate can take up approximately 5 gallons of space. And given the 1 inch 1-gallon rule, then 14 is the most appropriate number. If you are a novice, then anywhere between 12 and 14 is ideal for you. 

Now, how do you maintain the tank? Can you add other species? Which tank-type should you buy? Well, more on this in the following sections. Let’s dive in.

How Many Guppies Can You Have in a 20-Gallon Community Tank?

Guppies are compatible with various species ranging from platies, swordtails, and mollies, to cory catfish, to mention but a few. But how many will fit in a 20-gallon community tank? 

Well, this depends on the tank mate. While tetras are of the same size as the guppies, Plecostomus are larger which affects the ratio between the two. 

The trick is to strike a balance to avoid overcrowding. Likewise, you should opt for peaceful tank mates. Also, the number of guppies will depend on decorations and plants. 

What fish can you keep with guppies in a 20-gallon tank?

Some of the most compatible tank mates include:

  • Platies
  • Mollies 
  • Honey Gouramis
  • Cory catfish 
  • Harlequin Rasboras 
  • Bristlenose Pleco
  • Cardinal Tetra
  • Otocinlus Catfish
  • Kuhli Loach
  • Nerite Snails 

Also Read: What Do Guppies Eat

How Many Guppies Can You Have Per Gallon?

As earlier mentioned, experts recommend an inch of fish per gallon. An adult guppy measures 1 – 2 inches which means that you should keep a guppy per gallon. 

How Many Male Guppies Can I Put in a 20-Gallon Tank?

If you want a colorful aquarium, then you should aim to keep male guppies. They come with colorful splashes, stripes, or spots, compared to their grey female counterparts. 

So, if you are after an aesthetic touch, then put one male guppy per two gallons of water. As such, a 20-gallon tank should hold at least 10-12 fish. However, if you want to incorporate female guppies, the ratio should be 1:2 (one male per two females)

Can Guppies Mate in a 20-Gallon Tank?

Yes! A 20-gallon tank is an ideal place for guppies to mate. However, you should provide enough plants and decorations where fry will hide. Why? Because guppies tend to attack and eat fry after birth. Alternatively, you can separate the parents from the fry.

How do You Set Up a 20-Gallon Guppy Tank?

Setting up a guppy tank is easy provided you follow the following guidelines. So, let’s find out how the tank should look like.

Choose the ideal tank

In this case, a 20-gallon tank will serve the purpose. You will find our recommendation mentioned below!

Also Read: How Many Guppies in a 10 Gallon?

Fix a powerful filter 

For beginners, we recommend using an external filter to an under gravel filter. Most tanks come with a cutout at the back where you should install it. Opt for one that can filter at least 100 gallons of water per hour for a healthy aquarium. 

Filters help keep the water clean and free from bacteria and waste that poison the guppies. Before using it on your tank, rinse it with water from a guppies tank to equip it with good bacteria ideal for eliminating chlorine in tap water.

Also Read: Best Fish Tank Filters

Add substrate 

Once you have the filter in place, it’s time to add gravel. You can purchase this substrate from your local pet store. Add at least three inches of gravel to the bottom of the tank. 

Note: Never use gravel sourced from your backyard or other sources. It might introduce harmful bacteria in your tank. Also, check the gravel compatibility with live plants. 

Add water

Now, add water until the tank is half full. This will enable you to place decorations and live plants appropriately.

Introduce plants and decorations

Place decorations, rocks, and plants which are ideal hiding spots for guppies. Ensure that the rocks and decorations are deeply rooted in the gravel to avoid hurting your fish. Plants not only provide hiding spots but also filter toxins and give out oxygen enabling the fish to thrive. 

Introduce an air pump

Air pumps help aerate the water by increasing the agitation/water movement. As such the surface area for gas exchange is increased. Besides, some filters such as sponge filters will only operate with the inclusion of an air pump.

Also Read: Do Guppies Need an Air Pump?

Add a water heater

Guppies like most aquarium fish thrive in temperatures between 24 and 27 degrees. This is where a heater comes in handy to maintain this range. An automatic or adjustable heater is ideal and should be placed inside the tank. 

Also Read: 10 Best Aquarium Heaters Buyers Guide

Add a lamp

They require light during the day, therefore, you should opt for a light with timer. Set it to stay on for eight hours which is ideal for guppies. Without enough darkness, they become agitated and won’t develop optimally and without light, they’ll develop abnormalities. 

To recap:

  • Choose a 20-gallon tank
  • Add a filter
  • Add gravel
  • Add water (halfway full)
  • Introduce decorations, live plants, and rocks
  • Add an air pump
  • Add a water heater
  • Add light with timer

How to Keep a Healthy Guppy Tank?

Taking care of your guppies is a piece of cake. You just have to ensure that all water parameters are as recommended among other aspects. Let’s see how you can keep your guppies happy.

Provide an environment that will enable them to thrive

Although small, guppies require an environment where they can swim freely and hide when threatened. As such, you need a tank that will accommodate one guppy per gallon. Besides, there should be ample plants and decorations where it can hide and rest. An overcrowded aquarium can lead to premature death.

Strike the recommended ratio

If you are keeping males and females in the same tank, ensure that the ratio is 1:2 – for every male, there should be two females. Keeping more males than females will cause the males to harass and kill the females. 

Provide ample day and night time

As earlier mentioned, guppies need ample darkness and light to thrive. As such, ensure you provide at least eight hours of darkness. 

Feed the right food quantity 

Feed them with quality flakes twice a day. They should contain ample vegetables and proteins for them to thrive. 

Ensure optimum water parameters 

Ensure that the water has the following parameters:

Parameter Range
Temperature 24 – 27 degrees
pH 6.8 – 7.8
Hardness 8 – 12 dGH

Which are Some of the Best 20-Gallon Aquarium Tanks?

Tetra 20 Gallon Complete Aquarium Kit (link to amazon)

This tank is made of anti-scratch glass that keeps your aquarium neat all day long. Besides, it comes with an LED lighting system ideal for daylight and an ultra-quiet filter that keeps the water clean. 

Also, your guppies will enjoy stress-free swimming thanks to the provided decorations. All you have to buy separately is the substrate.

SeaClear Acrylic Aquarium (link to amazon)

This rectangular tank provides a large surface area for optimum gas exchange keeping the water oxygenated. It is lightweight, portable, and extremely sturdy allowing you to carry it around and keep your fish safe.

The rectangular shape and crystal clear glass enable you to watch your fish swim as well as admire the decorations without obstruction.

Aqueon Aquarium 20 Gallon Long (link to amazon)

If you want to add your preferred decorations, lighting system, and other accessories, then this should be the perfect choice for you. This sturdy tank allows you to add all that you want until you achieve an aesthetic touch. 

Elive Aqua Duo 20 Gallon LED Kit (link to amazon)

Next off is the Elive tank that couples as an aquarium and an Aquaponic. As such, you can plant an indoor in the provided slot. This allows the fish to provide nutrients to the plant through their waste while the plant acts as a natural filter.

As a result, you have a cleaner and healthier aquarium where your guppies can thrive. It also comes with an LED lighting system with a timer. Besides, it comes with bio planting media ideal for the filter.

Aq Ascent LED Kit 20g (link to amazon)

Lastly, we have this tank that comes with a powerful filtration system that keeps your tank free from waste and an LED lighting system that provides light to your guppies. 

The angled top provides a large viewing angle while eliminating the waterline. The floating base significantly bolsters its aesthetic touch.

Related Questions 

Which other fish are good for a 20-gallon tank?

Other fish that can thrive in such a tank include:

  • Swordtail
  • Molly Fish
  • Neon Tetra
  • Fancy Guppy
  • Zebra Danio

Which other animals are ideal for a 20-gallon tank?

Apart from fish, you can also put geckos such as Leopard geckos and crested geckos.

Also Read: Can Guppies Live with Bettas?

Final Say 

As you can see, a 20-gallon tank is ideal for keeping healthy guppies. However, you should aim to ensure you strike the right ratio of 1:2. Add compatible tank mates, and always keep water parameters as recommended. Keep the water clean as this improves the fish’s lifespan.