What You Need To Know When Stocking A 15-Gallon Tank
If you’re going to be setting up and stocking a 15-gallon tank you may be asking a few of the following questions:
- How many fish can be in a 15-gallon tank?
- What are the best fish for a 15-gallon tank?
- 15-gallon fish tank stocking ideas?
- How many Goldfish in a 15-gallon tank?
- How many Neon Tetras in a 15-gallon tank?
- How many Cichlids in a tank?
- How many Guppies in a 15-gallon tank?
- How many Platies in a 15-gallon tank?
- Good fish combinations for a 15-gallon tank?
Overall a 15-gallon tank is in on the low end of the mid-size tank range so you’ll want to be careful with how many and the types of fish you keep.
If you’re still wondering what you should do?
Good news!
Below we will answer all these questions and even show you some other tiny things that you can fit comfortably in your 15-gallon tank.
Let’s begin.
Table of Contents
A Few 15 Gallon Fish Tank Ideas
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Question #1
How Many Fish Can Be In A 15-gallon tank?
Ah, yup this question again!
And if I’m being honest it depends!
Seriously though, how many fish can you put in a 15-gallon tank?
Well, you should try to aim for one small fish per gallon of water and by “small” fish I mean like Tetra sized fish.
Basically, it equates to approximately 1 inch of fish per gallon.
But it’s not always that easy, you can see my thoughts on that here to see what I really think.
That said, you should be able to fit about 10-15 small fish in your tank at first and as the tank matures and you get better at fish keeping. You can maybe keep 15-25 if you don’t mind some work.
However, this is what most beginners do, they buy a 15-gallon tank and fill it with a few fish without doing a little bit of research.
But you’re not like most people and you at least asked the question, so good on you.
The problem most beginners don’t realize is that you need to consider a few things like;
- The growth rate for your fish
- Their temperament, how aggressive are they?
- How dirty are they
For example, a small goldfish can grow up to 6″ in size in less than a year.
Can you see a huge 6″ Goldfish living comfortably in a 15-gallon tank?
Maybe, but it’s getting cramped
That said, what if you could find a few examples of fish you could put in your 15-gallon tank?
Well, you’re in luck, that’s what I’ve prepared below.
Further Reading: Best freshwater aquarium fish
Question #2
What Are The Best Fish For A 15-Gallon Tank (Freshwater)
Below are a few of the Best Fish Species for a 15 Gallon Fish Tank?
- Small tetra species
- Cichlids
- Small Rasboras
- Dwarf Gourami species
- Bettas (Siamese fighting fish)
- Fancy Guppies
- Shrimps
To help we’ve split them into a few groups:
Community fish
- Platy
- Tetra
- Rasbora
- Corydora Catfish
- Guppies
- Dwarf Cichlids
- Shrimp
Schooling fish
- Small Tetras
- Rasbora
- Corydora Catfish
Aggressive fish
- Betta
Big fish
- Dwarf Cichlid
- Gourami
Hopefully, that was helpful, but if that list wasn’t BIG enough for?
No worries, just wait until you see the next list!
Question #3
15-gallon Fish Tank Stocking Ideas?
Alright, here it is, the biggest stocking list for a 15-gallon tank that I could create.
There are literally 40 fish you can pick from.
Tetra:

Photo Credit: Cliff
- Cardinal Tetra
- Ember Tetra
- Rosy Tetra
- Flame Tetra
- Glowlight Tetra
Rasbora:

Photo Credit: Drew Tyre
- Lambchop Rasbora
- Chilli Rasbora
- Glowlight Rasbora
- Harlequin Rasbora
- Least Rasbora
- Dwarf Rasbora
- Red Dwarf Rasbora
- Microrasboras Galaxy
Platies:

Photo Credit: Allie_Caulfield
- Parrot Platy
- Red Platy
- Coral Platy
- Red Diamond Platy
Guppies:

Photo Credit: Jorge Correa
- Endler Guppies
- Fancy Guppies
Cichlids:

Photo Credit: LEONARDO DASILVA
- Angel Ram Cichlids
- Electric Blue Ram
- German Blue Ram
- Yellow Dwarf Cichlid
- Apistogramma Borelli Opal
Gourami:

Dwarf Gourami Centerpiece Fish” width=”650″ height=”434″ />
Photo Credit: Bernat Arlandis
- Honey Gourami
- Dwarf Gourami
- Red Dwarf Gourami
- Sparkling Gourami
- Honey Gourami
- Sparkling Gourami
Corydoras Catfish:

Photo Credit: h080
- Panda Corydoras Catfish
- Albino Corydoras Catfish
- Skunk Corydoras Catfish
Shrimp:

Photo Credit: Emilia Murray
- Red Fire shrimp
- Tiger shrimp
- Cherry shrimp
- Amano shrimp
Misc:

Photo Credit: JellyFishKiller
- Betta Fish
- Scarlet Badis
- Dwarf Puffer
If none of the above species are what you’re looking for in terms of fish, well too bad that was a lot of work and maybe you need a larger tank.
Or you can check out one of these articles for more ideas:
That said, a larger tank is not only easier to maintain but will provide you with the opportunity to keep a wider selection of fish.
Alright now for the main event!
Question #4
What Are Some Good Fish Combinations For A 15-Gallon Tank?
In general, when stocking your 15-gallon tank try to have one or two larger “Centerpiece” fish and fill in the rest with a school of smaller fish and a few bottom dwellers like shrimp or catfish.
It’s really up to you!
Here are a few suggestions you can try:
Combo-One: The Betta Tank
- 1 Betta Fish
- 8-10 Harlequin rasbora
- 4 Panda Corydoras Catfish
Combo-Two: The Ram Tank
- 1 pair (m/f) Electric Blue Rams
- 8-10 Ember Tetra
- 4-6 Albino Corydoras Catfish
Combo-Three: The Gourami Tank
- 1 pair (m/f) Dwarf Gourami
- 8-10 Glowlight rasbora
- 8-10 Cherry Shrimp
Lastly, if you’re a beginner you could try setting up a low-tech planted tank with a few live plants.
This will help keep the water quality in check and prevent spiking.
Some great beginner plants are;
- Java Fern
- Javal Moss
- Anubias
In a 15-gallon tank try;
- 2-3 x Java Fern
- 6 x Anubias
- 2-3 x Java Moss Ball
Overall a fifteen-gallon tank is a great size for a beginner to start a small community tank!
And always remember It’s important to understand the nitrogen cycle and how to maintain healthy water conditions for your fish.
Question #5
How Many Goldfish In A 15-Gallon tank?
You’ll notice that out of all the fish I listed above the Goldfish was not one of them. That’s because they need more space than a 15-gallon tank.
Seriously, they poop a lot and grow way too big, don’t do it! Seriously don’t.
Question #6
How Many Neon Tetras In A 15-Gallon Tank?
Neon Tetras are great little fish that will provide little shimmers of colorful excitement in your tank.
If you only kept Neons in the tank you could fit about 10-20 Neon tetras comfortably in a 15-gallon tank or you could use some of these tank mates with Neon Tetras.
Question #7
How Many Cichlids In A 15-Gallon Tank?
For a tank this size I would recommend you only keep some of the more docile Cichlids like Dwarf Cichlids, Rams or Apistogramma (see the list above).
It would also be best to only keep 1 pair (m/f) of the same species and then fill in the tank with some smaller tank mates.
Further Reading: Cichlid Tank Mates
Question #8
How Many Guppies In A 15-Gallon Tank?
Guppies are great little fish especially the Fancy and Endler varieties which are available in so many different colors and combos.
You could fit about 6-12 guppies in a 15-gallon tank. But like I said earlier keep with one sex to avoid any unwanted babies.
Question #9
How Many Platies In A 15-Gallon Tank?
With Platies you’ll want to keep about 4-6 with a mix of male and female, just be sure to have more females than males to avoid aggressive behaviors.
Here are a few more articles you will find useful when looking at stocking some smaller-sized tanks.
- Fish For A 1 Gallon Tank (10 Best Fish)
- Fish For A College Dorm (Student Friendly Options)
- Fish For Your Office (Cubicle Friendly Options)

- API Freshwater Master Test Kit Instructions Your Guide to Aquatic Success - November 9, 2023
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