10 Best Freshwater Fish for a 75-Gallon Aquarium

Posted by on 2/17/2024

Whether you’re in a local fish store, shopping online, or wandering through a chain pet store, there are certain fish that you can almost always count on finding for sale.

Throughout the years, certain species of aquarium fish have caught the attention of new and experienced hobbyists, and it’s for good reason. In this post, we’re going to count down the most popular aquarium fish, and we’ll even discuss why some of these species are so popular. Let's begin!

Schools vs Centerpiece Fish

One of the first decisions you'll want to make when stocking a tank this size is whether or not you should keep a large school of fish or a few centerpiece fish. 

While it may be fascinating to observe the behavior of a wide variety of larger-sized centerpiece fish, housing a large amount of small-sized fish can be quite rewarding. Many aquarium fish will school (technically, they shoal), and witnessing a group of fish moving in unison is a sight to behold in an at-home aquarium!  

Our 10 Favorites

Now that we've covered the pros and cons of owning schooling fish and centerpiece fish, let's get into some of our favorites.

Electric Blue Jack Dempsey

At 75 gallons, hobbyists can care for cichlids. For those unaware, cichlids are a subcategory of freshwater aquarium fish that have achieved a massive fan base throughout the years. There are many different types of Cichlids, categorized by location, such as African Cichlids, and South American Cichlids, but one of our all-time favorite cichlids has to be the Electric Blue Jack Dempsey

This fish tends to be a bit more peaceful compared to the more common Jack Dempsey fish and displays a brilliant electric-blue coloration. Adults will grow to about 7 inches in length, and tank mate options include other cichlid species, such as the Blue Acara and Convict Cichlid.

Electric Blue Jack Dempsey
An Electric Blue Jack Dempsey

Green Spotted Puffer

One of the most photographed fish in the hobby is the Green Spotted Puffer. The fish makes an excellent centerpiece fish, but due to its aggressive temperament, you'll want to avoid adding any additional tank mates.

Interestingly, Green Spotted Puffers are capable of living in a marine environment, making them a good choice for hobbyists considering a transition to the saltwater side of aquariums.

Green Spotted Puffer
A Green Spotted Pufferfish


A 75-gallon tank allows you to keep the holy grail of freshwater fish, Discus. Hobbyists can keep up to 7 adults in a 75-gallon tank, and there's no shortage of beautiful color morphs to choose from. Pigeon Blood, White, Checkerboard, and our favorite, the Blue Diamond Discus are all amazing choices for hobbyists looking to get into the world of discus keeping.

Be warned: Discus are expensive and difficult to care for, so make sure you do A LOT of research before considering Discus as your next tank addition.

Discus, native to the Amazon

Gold White Cloud Mountain Minnow

Remember how earlier we mentioned schooling fish vs centerpiece fish? Enter the Gold White Cloud Mountain Minnow, the first schooling fish on our list. Native to China, these fish sport an orange coloration, making them quite different compared to the traditional white cloud mountain minnow.

Hobbyists can keep up to 70 of these fish in a 75-gallon tank, and their playful and active temperament will be sure to catch the attention of those lucky enough to see your tank!

Gold White Cloud Mountain Minnow
Andrej Jakubik/Shutterstock.com
A Group of Gold White Cloud Mountain Minnows

Eques Corydoras

For hobbyists looking for a rare and unique bottom-dwelling fish, look no further than the Eques Corydoras. These fish are expensive and hard to find for sale, but their beautiful appearance makes them highly desired for those who are in the know. Hobbyists can keep a small group of 5-10 of these fish in a 75-gallon tank in addition to other peaceful species.

However, if the Eques Cory is too difficult to find for sale, we have a list of popular bottom-feeding fish that make great alternatives.

Eques Cory
Pavaphon Supanantananont/Shutterstock.com
An Eques Corydora

Boesmani Rainbowfish

Next up on our list is the Boesmani Rainbowfish. These fish are known for their torpedo-shaped bodies and beautiful appearance, and hobbyists with a 75-gallon tank should have no issues keeping up to 15 of these gorgeous fish. Males tend to be a bit aggressive depending on the number of available females, so aim for at least 1 male for every 2 females if you plan on keeping a group of these Rainbowfish.

Boesmani Rainbowfish
Mark Brandon/Shutterstock.com
A Boesmani Rainbowfish

German Gold Rams

While Rams have a reputation for being aggressive, a 75-gallon aquarium gives you plenty of space to work with. These fish tend to be a bit territorial and are kept in pairs, 1 male for each female. Hobbyists should be able to keep at least 2 pairs of German Golds in a 75-gallon tank, but you'll want to monitor for aggressive behavior. These fish also prefer warmer temperatures (78-86°F) something you'll need to consider if you plan on adding other types of fish to your tank.

German Gold Ram
FishyRamGuy/Light Fish
German Gold Rams


Similar to Discus, freshwater Angelfish are another sought-after species pursued for their unique coloration. Black Marble, Koi, and Platinum are just a few of the many color morphs available for these unique fish. Similar to German Gold Rams, you'll want these fish to pair up. At 75 gallons, you can have a maximum of 2 male: female pairs. You'll want to ensure you have a successful pair-up before adding 2 additional fish, that way you'll minimize the risk for any territorial disputes.

You Touch Pix of EuToch/Shutterstock.com
An Angelfish (scientific name: Pterophyllum scalare)

Spotted Blue Eye Rainbowfish

If you're looking for a rare small-sized schooling fish, then look no further than the Spotted Blue Eye Rainbowfish (scientific name: Pseudomugil gertrudae). These fish are significantly smaller than the previously mentioned Boesmani rainbowfish, as adult Spotted Blue Eyes only reach a maximum size of about 1.5 inches in size. These fish are known for their active personalities, and hobbyists lucky enough to get their hands on some of these fish can keep up to 50 of these fish in a 75-gallon. Plus, their peaceful temperament makes them an excellent community fish member for those looking to add freshwater inverts or other bottom dwelling fish to their tanks.

Spotted Blue Eye Rainbwofish
Der Regenbogenfisch/Wikimedia Commons
Spotted Blue Eye Rainbowfish

Blue Emperor Tetras

While cardinal tetras and green neon tetras tend to be some of the more popular tetra fish, a lesser-known tetra species known as the Emperor Tetra makes for an excellent 75-gallon aquarium addition. Interestingly enough, a rare color morph exists known as the Blue Emperor Tetra. Hobbyists lucky enough to find these fish for sale can have up to 50 of these fish in a 75-gallon tank, and their bright coloration and playful personalities make them always in demand by hobbyists. However, if you can't find the Blue Emperors, the standard Emperor Tetras are just as rewarding to keep. Similar to the Spotted Blue Eye Rainbow and Gold White Cloud Mountain Minnows, the Blue Emperor Tetra is an excellent schooling fish.

A Blue Emperor Tetra
Pavaphon Supanantananont/Shutterstock.com
A Blue Emperor Tetra

Where to Purchase

If you're looking to find some of the fish for sale on our list, be sure to check out our marketplace, where you can buy and sell directly with aquarium hobbyists just like yourself.

However, if you can't find exactly what you're looking for, we built a massive list of over 250 different online aquarium stores to help you in your search.


That concludes our list of our 10 favorite freshwater fish for a 75-gallon tank. Whether you decide to go for a large school of small fish, or a small group of larger-sized fish, a 75-gallon aquarium gives you tons of stocking options to choose from.

While we only covered 10 different options, there are TONS of additional fish and aquatic inhabitants to choose from. Do you have a favorite fish that didn't make the list? Let us know in the comments, and be sure to visit our marketplace where you can support others in the aquatic hobby.

Image of Miles Harrison

Miles Harrison

With over a decade of aquarium experience, Miles can be found writing about saltwater and freshwater aquariums. When he’s not writing about fish, you can find him going for a run or building websites, such as this one!