How Many Glofish In A 3-Gallon Tank? Zero!

Dec 29, 2021

How Many Glofish In A 3-Gallon Tank

The irony is that the largest tank sold for glofish has a 10-gallon capacity, but a single glofish shark needs at least 50 gallons. I was dumbfounded with the amount of misinformation littered on the net regarding raising glofish – even from their own creators. So, how many glofish in a 3-gallon tank? Is it even doable?

Find out the truth. 

How Many Glofish In A 3-Gallon Tank? 

Unfortunately, you can add exactly 0 glofish in a 3-gallon tank. Technically, you can fit 1-3 glofish tetras and danios in a tank that small, but we highly, very highly recommend against it. 

There are basically five glofish species – tetras, danios, barbs, bettas, and sharks – and none of them are suitable for a 3-gallon tank. 

Let me tell you why. 

Why Can’t You Keep Glofish Tetras In A 3-Gallon Tank?

As I stated above, you can keep a couple of glofish tetras in a 3-gallon tank. But the reason we don’t recommend it is because tetras are schooling fish that find safety in numbers. 

Ideally, you should keep them in a group of 5-6 – the more, the better. And a 3-gallon tank can’t house that many of them. 

On top of that, glofish tetras are very active fish that love to swim around and explore all day. A small tank will not only bore but profusely stress them out. 

As a result, they will become aggressive and fight with their own kind.

Minimum Recommended Tank Size For Glofish Tetras

The minimum recommended tank size for a small school of glofish tetras is 15 gallons.

Why Can’t You Keep Glofish Danios In A 3-Gallon Tank?

Glofish danios are small fish, barely reaching 2 inches long in captivity. However, they are the most hyperactive fish in the glofish family. 

They love to pace and dart around the tank. So, a 3-gallon tank simply doesn’t have enough space for them to perform acrobatics. 

Moreover, like tetras, glofish danios are schooling fish. Just keeping 1, 2, or 3 of them will not suffice. It will stress them out. 

Minimum Recommended Tank Size For Glofish Danios

The smallest recommended tank size for glofish danios is 10-gallons.

However, a 20-gallon long tank would be perfect for a small school of these fish. 

Why Can’t You Keep Glofish Barbs In A 3-Gallon Tank?

Glofish barbs are created from tiger barbs that are notorious for their aggression. So, there’s no way you can keep them happy in a 3-gallon tank. 

Even though glofish barbs don’t grow any bigger than 3 inches, they need a big tank to mark their tiny territories. 

If there’s not enough space, glofish barbs will resort to aggression. They will nip each other’s fins, involve in duels, and even potentially kill. 

Also, don’t forget they’re schooling fish as well. 

Minimum Recommended Tank Size For Tiger Barbs

The smallest tank you can get for your tiger barbs is 20 gallons. But if possible, I’d suggest getting a 30-gallon tank. 

Why Can’t You Keep Glofish Bettas In A 3-Gallon Tank?

Bettas are the poster child of fish suitable for tanks as small as 1.5 gallons. Your betta may survive in a tank that small, but they will lead an impoverished life. 

Bettas may not grow too big, but they’re territorial and aggressive. After all, they weren’t named Siamese fighting fish for no reason.

A small 3-gallon tank simply does not have enough room to happily keep even a single betta fish. 

Minimum Recommended Tank Size For Betta Fish? 

In my opinion, a 5-gallon tank would be the bare minimum for a single betta fish.

If you want to keep multiple males in the same tank, you will need a massive tank complete with plenty of hiding spaces and possibly a tank divider. 

Why Can’t You Keep Glofish Sharks In A 3-Gallon Tank?

Keeping a 6-inch-long glofish in a 3-gallon tank is out of the question. These fish are known for their angry disposition. 

They’re also quite active and love to swim around a lot. 

So, if you keep them in a small tank, the fish will lead an impoverished life as they will be stressed and agitated at all times. 

Minimum Recommended Tank Size For Glofish Shark

The minimum recommended tank size for a single glofish shark is 50 gallons. If you plan to keep any more than that, the tank’s capacity should be 125 gallons or upward. 

Recommended Readings!

How Many Glofish In A 20-Gallon Tank? Honest Answers!

How Long Can Glofish Go Without Food? Which Species Can Go The Longest?

How Big Do Glofish Get? What Tank Size Do They Need?

What Do Glofish Eggs Look Like? Photos And Videos!

To give you well-rounded information on one platform, I scoured through half a dozen forums and looked up what real hobbyists like you and I have to tell. 

Here are their answers on how many glofish can go inside a 3-gallon tank. 

How Many Glofish In A 3-Gallon Tank? Real Answers By Real People! 

Note: All the opinions expressed below belong to the respective authors. 

“I hate to say this, but unfortunately, a 3-gallon tank cannot really support much of anything. With plants and a small heater, it might be able to house a couple of cherry shrimps but not glofish.”

“If you want to raise glofish, you need a 20-gallon tank – anything smaller, and it will not be a happy or a pretty tank.”

“A tank that small is only suitable for some miniature shrimp. It just does not have enough room or biological load capacity for glofish. A 20-gallon tank would offer a much safer environment.”

“An aquarium that size is not suitable for any single fish, much less a group.”

“No fish should ever be kept in a tank that small. It will be too difficult to maintain a proper biofilter, and the fish will inevitably suffer. I know there are specially designed glofish tanks that are that small, but they’re neither safe nor appropriate.”

“Unfortunately, the short answer to your question is 0 fish.”

Frequently Asked Questions 

yellow glofish
Credits: Ho-Wen Chen (CC license)

How Many Glofish In A 5-Gallon Tank?

You can keep around 2 glofish tetras, bettas, and danios in a 5-gallon tank. But even that would be a stretch. If I were to be honest, I’d say 0. So my suggestion would be to get at least a 20-gallon tank or upwards. 

How Many Glofish In A 10-Gallon Tank?

You can keep 5-6 glofish tetras, 2-3 female glofish bettas, 4-5 glofish danios in a 10-gallon tank. Unfortunately, you can’t keep glofish barbs and sharks in a tank that small. 

How Many Glofish In A 20-Gallon Tank? 

You cannot possibly keep glofish sharks in a 20-gallon tank. But you’re in luck – you can keep 8-10 glofish tetras, 10-12 glofish danios, 5-6 glofish barbs, and 4-6 female glofish bettas in a 20-gallon tank. Not together, of course! 

How Many Glofish In A 40-Gallon Tank?

Once again, a 40-gallon tank isn’t enough for glofish sharks. They need 50 gallons minimum. However, you can have 18-20 glofish tetras, 20 glofish danios, 8 female glofish bettas, and 12-13 glofish barbs in a 40-gallon tank. 

Final Words: How Many Glofish In A 3-Gallon Tank? 

Sorry to be the killjoy here, but you cannot keep any of the 5 glofish species in a 3-gallon tank. 

At a minimum, glofish tetras need 15 gallons, glofish danios need 10 gallons, glofish barbs need 20 gallons, glofish bettas need 5 gallons, and glofish sharks need 50 gallons! 

If you keep your glofish in a 3-gallon tank, it’s not just the fish that will suffer. A 3-gallon tank will constantly keep you on your toes with frequent water tests and changes. 

A 3-gallon tank neither has enough room for swimming or some honest mistakes! 

So, go bigger! Trust me on this one! 

Recommended Readings!

How Many Glofish In A 10-Gallon Tank? Zero?

How Long Do Glofish Live? Which Glofish Species Lives Longest?

How Big Do Glofish Tetras Get? Grow Them Fast!

rohit gurung author at urbanfishkeeping

About Rohit Gurung

My never-ending love and fascination with Aquascaping started when I received a red-eared turtle for my 10th birthday.

Apart from researching and writing, I spend hours gazing at my 3 turtles. And yeah, I bask alongside them too.