A 75-gallon tank isn’t for everybody. Creating a stable and thriving aquatic environment is tricky enough as it is. Getting your aquarium to 75 gallons is pouring fuel over a fire.
The extra space will come with various challenges, including financial in nature. You will naturally need more substrate, more plants, more decorations, more rocks, and, of course, more fish.
On the other hand, a 75-gallon setup is more self-sustainable and easier to maintain than smaller tanks.
That’s because the environment is larger, which means that the chemicals get cycled around more effectively. But what fish should you use for your 75-gallon aquarium?
Stocking Ideas for 75-Gallon Tank
You can stock 75 gallons planted tank with various fish species such as angelfish, discus, tetras, livebearers, gouramis, ram cichlids and rainbowfish. All these fish species do really well in planted tanks and don’t eat plants.
Angelfish
The angelfish grows up to 6 inches and gets its name from its wide and loose fins, imbuing the fish with an angelic presence. This species is a great addition to larger setups and can live up to 12 years with optimal care.
They are feistier and more energetic than many other species, as they patrol their environment relentlessly during the day. Part of that is due to their territorial tendencies and high energy during the breeding season.
Fortunately, the angelfish is hardy and adaptable and can cope with a variety of environmental conditions.
Environmental Requirements
These are tropical fish, so you need to provide them with adequate temperatures to keep them active and healthy. Angelfish prefer higher temperatures in the neighborhood of 75 to 84.
They can withstand some slight variations, but not by much. The fry require higher temperatures since they display a more accelerated metabolic rate. Providing them with temperatures above 82 will boost their growth rate considerably.
Other than that, you should provide your angelfish with various plants and decorations, as long as they’re safe. Angelfish possess long and wide fins, making the fish vulnerable to sharp or rugged decorations.
Stiff and abrasive plant stems could also damage their fins, especially since the angelfish is quite an active species.
Overview
Consider the fish’s tankmates carefully. The angelfish likes to live in schools of at least 4-6 specimens, but this may differ. Angelfish may differ in terms of personality and overall behavior.
These fish rank as semi-aggressive, so fighting each other over space, food, or reproductive dominance is not uncommon.
Don’t pair them with fin nippers since these can stress out your angelfish, affecting their health in the long run. Livebearers make for decent tank mates, especially since the angelfish will eat their fry, keeping their population under control.
I’m thinking guppies, but you can also use other species, like tetras, cory catfish, mollies, etc.
Discus Fish
This cichlid grows up to 8 inches, although you’ll most likely get it at 6 max. Discus fish are intelligent, peaceful, and slow swimmers that will adapt to their environment quick.
They make for great aquarium pets, thanks to their adaptability and resilience, but they’re rather shy.
These fish display an astounding variety of colors and patterns and can even change their colors under some circ*mstances.
Environmental Requirements
This freshwater cichlid requires temperatures around 82 to 88 F, which is higher than most tank fish prefer.
Given that the discus fish is shy and easily startled, I recommend decorating their habitat with plants and underwater decorations.
Most importantly, remember that, as a cichlid, the discus fish requires ideal environmental conditions to remain healthy and active.
You need to embrace a robust tank maintenance routine to keep the water fresh and clean in the long run.
This makes the discus fish more difficult to care for than other species. So, I only recommend this species if you’re already experienced in the fish-growing business.
Overview
You can easily house 7-10 fish in a 75-gallon setup, provided no other tankmates are present. Finding the right tankmate for them can be a challenge. Avoid fast, aggressive, or overly inquisitive fish that could stress or bother your discus too much.
The ideal tankmate is a slow swimmer with a friendly temperament and similar environmental requirements.
It’s also important to note that discus fish are naturally territorial, as is the case with cichlids in general. So, they tend to get into territorial fights if they feel crowded or stressed out.
A tank layout consisting of multiple caves, rocks, plants, and other hiding areas is necessary to mitigate their aggression and keep them calmer.
Tetras
Tetras make for a great addition to any aquarium, no matter the size. But I think they will fit a larger tank even better because they are relatively small and display schooling behavior.
These fish will only grow up to 1.5 inches and don’t need much care to thrive. They rank as hardy and resilient fish, capable of adapting to a variety of setups.
Environmental Requirements
Tetras require stable temperatures around 70-80 F. They have quite a generous temperature range, thanks to their astounding resilience.
The minimum tank size for these would be 10 gallons for a small school, but you can fit a lot more in a 75-gallon setup.
In fact, I don’t think you can create a 75-gallon environment for tetras only. I mean, you can, but there’s no point in doing that. Tetras are small and active fish that thrive in pretty much any environment.
There’s no point in having 30-40 tetras in a 75-gallon tank unless you are absolutely enamored by them.
Otherwise, I advise finding them some compatible tank mates for a plus of visual and social diversity. Tetras don’t mind the presence of other fish species, provided there’s enough room for all of them.
Overview
Tetras show a maximum lifespan of 8 years in captive conditions in the ideal conditions. They only need stable temperatures, clean waters, and a variety and optimized diet and won’t ask for much else.
These fish display an astounding color and pattern diversity, providing you with a wide selection pool.
When looking to accommodate your tetras to their new environment, consider the following:
- Tetras demand low-light conditions
- They need an omnivorous and varied diet to remain healthy
- Don’t pair them with fish with large fins because tetras are notorious fin nippers
- Despite their hardiness, tetras are vulnerable to diseases like Ich and fin rot; so impeccable water conditions are necessary to prevent those
- The ideal tankmates for tetras include barbs, gouramis, cory catfish, other tetra strains, etc.
Livebearers
Livebearers from the most popular group of fish today. The notion of a livebearer refers to the fish’s reproductive behavior. Some fish lay eggs, while others produce live fry after the eggs hatch inside their bodies.
So, technically speaking, livebearers are also egg layers. It’s just that they don’t lay the eggs but have them hatch inside them.
The most notable livebearers include guppies, mollies, platies, and swordtails, to name a few.
Their most distinctive characteristics include:
- An omnivorous diet, making them easy to feed
- Adaptability and resilience to various environmental conditions
- Schooling or shoaling behavior, allowing the fish to find strength and safety in numbers
- A shy but friendly and calm demeanor, making them perfect tankmates for a variety of species
- The highest color and pattern diversity, especially for guppies
- The easiest fish to breed in captivity available today
- The ability to produce fry every month, often in the hundreds with each spawn
Needless to say, livebearers are ideal for a 75-gallon tank since this provides them with more space than they could ever need.
After all, most livebearers only grow up to 2-2.5 inches. So, you can keep multiple schools in the same setup.
Environmental Requirements
Aim for temperatures around 72-82 F. These should accommodate most livebearer species. Heavily-planted setups are also recommended since these fish are easy to intimidate.
More aggressive, territorial, or curious fish can stress them out, at which point they may feel the need to flee and hide.
Add sufficient plants and decorations to keep the fish safe. Doing so will make them more prone to roaming their environment and greatly boost their coloring.
Overview
Livebearers can be territorial towards one another if they feel crowded or during the breeding phase. Males are especially dominant and aggressive towards each other.
So, always monitor their interactions and try to mitigate their behavior if their violent outbursts become too frequent.
Also, keep in mind that livebearers are often used as feeder fish due to their small size and breeding prowess. Choose their tankmates carefully. Pairing them with the wrong fish species can quickly turn your livebearers into prey.
Gouramis
Gouramis make for a special entry due to the fish’s astounding diversity. Not only do gouramis differ wildly in terms of color and patterns, but they also differ based on size.
A gourami could measure between 3 and 28 inches, depending on the species.
This means that you need to pick your gourami carefully since they have different needs based on their size. This can be a serious challenge in and of itself, considering that we have around 90 species of gouramis today.
These are the result of human-guided selective breeding, aiming to prioritize certain features and traits.
The fish’s lifespan varies based on numerous factors, such as water conditions, diet, and, most importantly, the species. Some gouramis only live up to 3 years in captivity, while others can go as far as 8 years.
Environmental Requirements
The ideal water temperature sits at around 72-82 F with a water hardness of 15 dGH tops. These are standard requirements that apply to most tropical fish.
This means that finding the right tankmates for your gouramis should be easy enough.
Gouramis are labyrinth fish that can breathe atmospheric air at the water’s surface. They are similar to bettas in this sense.
So, you should consider this trait when creating their environmental layout. Gouramis are mid-to-top dwellers, so you need to make sure that they have easy access to the water’s surface.
Overview
These fish are omnivorous and hardy for the most part. They will take time to adapt to a new setting, but once they do, they will thrive.
Just remember to pair them with peaceful and slow-swimming fish that will reflect the gourami’s own personality.
Over-active fish will cause the gouramis to starve since they won’t be able to keep up during feeding time. Some of their best tankmates include the danios, Corydoras, rasboras, and tetras, to name a few.
Bottom-dwellers like plecos or other catfish are also welcomed since they will rarely cross paths with the gouramis. Especially in a 75-gallon environment.
Also, remember that make gouramis are extremely territorial and competitive towards one another. You might want to separate them and only keep a harem (one male and several females) in your 75-gallon setup.
If you do want to keep more male gouramis, make sure there are at least 3-4 females for each of them. And that they have plenty of space to go around.
Rainbowfish
Omnivorous, peaceful, colorful, and easy to care for. These characteristics make the rainbowfish one of the most beloved species you can get.
There are around 50 different types of rainbowfish to choose from, many of which are the result of selective breeding.
The rainbowfish is easy to maintain and can tolerate an impressive range of water conditions. They can live up to 8 years with proper care, although the average sits at around 6.
Environmental Requirements
Go for a water temperature of 74-80 F for your rainbowfish with hardness values up to 20 dGH. Their ideal environment is one with fast-moving waters since these fish love to swim against the current.
This means that their tankmates should prefer the same conditions.
The minimum advisable tank size is 15 gallons for a small school. So, 75 gallons are more than enough to fulfill the fish’s needs. Remember, these are schooling fish that rely on their numbers for safety.
They need to have sufficient space at their disposal, especially since they’re some of the most active swimmers you can get.
Overview
Rainbowfish are notorious for their high energy levels. So much so that they’re made a reputation for themselves as jumpers.
Rainbowfish will jump out of your tank if they’re stressed, starved, or simply crowded and feel the need to explore outside of their habitat.
So, always have a lid on to prevent them from jumping out.
Their ideal habitat is planted and with steady water currents – a setting which may be difficult to achieve, given that most plants don’t fare well in fast-moving waters.
I recommend anubias, hornwort, or Amazon swords as good candidates in this sense, but feel free to experiment with other species as well.
Ram Cichlids
Ram cichlids, or German blue rams, are notorious in the aquarium world thanks to their beauty and astounding presence. This species is very much atypical, considering the profile of cichlids in general.
In short, ram cichlids are friendlier and more peaceful than other cichlids, although they are similar in many other areas.
Ram cichlids remain small, in the neighborhood of 3 inches in the case of males. They are omnivorous and live up to 3 years with adequate care.
Environmental Requirements
In typical cichlid fashion, ram cichlids prefer higher temperatures (around 80-86 F) and demand a variety of hiding areas.
Especially since these cichlids are shier than other species.
A rocky setup is ideal for them, preferably with a lot of caves, rocks, driftwood, and plants. Keep in mind that ram cichlids, and cichlids in general, are mid-to-bottom dwellers.
They will rarely reach the water’s surface, so you need to feed them sinking pellets.
Also, don’t pair them with overly active top dwellers since these will eat the cichlids’ food, causing them to starve as a result.
Overview
Ram cichlids are highly intelligent and will begin to recognize you over time. Despite being relatively shy, these cichlids are also active swimmers, so they need a lot of open space as well.
While they are generally peaceful in their ‘off-season,’ males can get feisty and territorial during the mating-and-breeding phase.
It’s worth noting that ram cichlids are very sensitive to the water’s quality. They are also vulnerable to some conditions like fish tuberculosis, Ich, fin rot, and skin flukes.
Fortunately, the primary trigger of these conditions is poor water quality.
Monitor ammonia levels, clean their tank regularly, remove fish waste and food residues, and perform partial water changes weekly.
Also, choose the cichlids’ tankmates carefully. Avoid aggressive or territorial species and stay away from dirtier species like goldfish.
These are notorious for producing a lot of poop, fouling the habitat more often than you would like.
Conclusion
A 75-gallon setup is designed to make an impact. Naturally, your first instinct is correct – create a lush, carefully crafted setting for the most impact.
In this sense, every detail counts. This includes the plants to use, the overall layout, the substrate, and the fish species.
I’ve provided you with several fish options to consider, but there are many more that could fit the requirements.
Just make sure they’re compatible with one another regarding water requirements, temperament, diet, etc.
