How To Breed Glofish? Will You Land In Jail?

Jan 26, 2022

How To Breed Glofish

Glofish apparently account for 10% of all aquarium fish sales as of late. So, I assume there’s a good population of them out there. But aren’t glofish nervous breeders that devour their own eggs? So, how to breed glofish successfully?

Even more, is it even legal to breed them?

I’ll answer all of these queries and some more today.

So, buckle up! 

Before we dive into the nitty-gritty of breeding glofish, let’s tackle an important question first. 

Is It Illegal To Breed Glofish?

The official GloFish website states that intentional breeding and any sort of sale, barter, or trade of glofish offspring is strictly prohibited. 

However, if you have glofish of both sexes present in your aquarium, sooner or later, they will most probably produce some young fry. 

And when that happens, I doubt you’ll receive a legal notice from Spectrum Brands or have two policemen knocking on your front door with handcuffs ready. 

If your glofish ever yield you little fry, just make sure you don’t sell or trade them. Let’s stay in the safe lane, right? 

And by the way, do you know glofish are altogether illegal in California? 

Also, Australia, Canada, and several European countries have banned sales or production of glofish. 

Hmmm… people really do have a strong opinion about genetically modified fish, don’t they?

Now, let’s answer the heart of the matter. 

How To Breed Glofish?

All 5 glofish species are egg-scatterers. And they are known to eat their own eggs right after laying them. So, frankly speaking, breeding glofish is tricky. However, if you do certain things right, you can readily breed glofish barbs, danios, tetras, and bettas at home. 

But guess what – there hasn’t been a single reported case of successfully breeding glofish sharks in captivity.

I don’t want to demoralize you, but maybe you and I can only breed glofish sharks when pigs have wings. 

How To Encourage Glofish To Breed?

Offering protein-rich food like live foods, brine shrimp, and frozen bloodworms encourages glofish to breed. Performing a big water change does the trick too. 

Now, let’s go into the details of breeding for each glofish species one by one. 

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What Glofish Can Live Together? 2022 Compatibility Guide

How To Breed Glofish Bettas?

Breeding glofish bettas isn’t a tough feat. If you’ve bred regular bettas in the past, chances are that you can successfully breed glofish bettas as well. However, glofish bettas are nervous breeders. So, things can go south pretty quickly in inexperienced hands. 

Glofish bettas reach sexual maturity at the age of 6 months or so. And it’s pretty easy to tell males and females apart. Males are blessed with long, flowy fins – and females look quite drab compared to males. 

Setting Up Your Glofish Betta’s Breeding Tank 

A 10-gallon tank would suffice to breed glofish bettas. Fully cycle the tank and ensure the breeding tank’s water parameters closely mirror the main tank’s. Adding plants will provide protection and food for young fry later on. 

Once the tank is set up, introduce a male and female betta into the tank. Both parties will be reasonably nervous in the beginning. So there’s a good chance they’ll get aggressive. Keep an eye out. 

Glofish Betta’s Mating Ritual 

Female glofish bettas will remain gravid for 1-2 weeks in general. 

When ready to make some babies, male glofish bettas will create bubble nests on the water’s surface. 

A bubble nest is basically a fizz of air pockets the male creates to woo the female first and later incubate the eggs. 

Once the female betta is impressed with the majestic bubble structure, she will consent to spawn. Then, the male will wrap his flowy fins around the female – this process is known as a nuptial embrace. 

He will gently squeeze the female betta’s abdomen so that she can lay the eggs. The female can lay anywhere between 100-500 eggs. 

The male will then fertilize the eggs, collect them with his mouth, and incubate them in the bubble nest he created. It’s once again best to remove the parents as the eggs hatch. 

It’ll take anywhere between 2-3 days. 

How To Breed Glofish Sharks?

Breeding glofish sharks successfully is an arduous task. The sheer intolerance for each other in captivity makes breeding next to impossible. However, in professional settings, breeders often inject certain hormones into the sharks’ bodies to encourage them to breed. 

Nonetheless, here’s a detailed guide on the breeding process. 

Setting Up Your Glofish Shark’s Breeding Tank

To breed glofish sharks, you need a big tank. It should at least be sized 75 gallons or higher. But, of course, the bigger is always better. 

First, fully cycle the tank to ensure its parameters are on par with the main tank. 

You must add plenty of rocks, caves, and plants. Since the situation may get heated in the tank, your sharks will need some quiet places to retreat to. 

The water temperature should be maintained between 72-82 degrees F. 

And if you plan to raise fry in the same tank, it’s advised to use a sponge filter to not suck in the fry. 

Glofish Shark’s Mating Ritual

Once the tank is fully prepped to host your sharks, transfer the bonded pair into it. Carefully monitor their behavior for a week to ensure they are getting along well.

Keep in mind that things can go south pretty fast. If they start attacking and chasing each other, you’ll have to separate them and try your luck with another pair. 

The female shark will carry eggs in her ovipositor for 1-2 weeks before laying them. 

Once ready to spawn, the sharks will start circling each other and rub against one another’s bodies. 

The matriarch will then lay over 100 adhesive eggs – a few at a time. The male will then spray the eggs with milt. 

Once the eggs are fertilized, immediately remove the parents as they’ll leave no stones unturned to eat their own eggs. 

As for eggs, you can transfer them to a 10-gallon tank using a nylon net. 

The eggs will hatch within the next 36-48 hours. 

How To Breed Glofish Danios?

pink and orange glofish
Credit: Ho-Wen Chen (CC license)

Glofish barbs are egg-layers that have a big appetite for their own eggs. However, they’re still relatively easier to breed than other glofish species. Since they don’t make the best parents, you still need to be cautious around the breeding time. 

Setting Up Your Glofish Danio’s Breeding Tank

A tank sized 10 gallons will be enough for breeding glofish danios. Fully cycle the tank and mimic the same water parameters as the original tank. 

And install a sponge filter, so it doesn’t suck in the eggs or fry. 

Adding a few plants here and there won’t just provide a retreat for your tiny fry but also serve as a food source during dire times. 

For substrate, add marbles. This will allow the eggs to fall between the cracks before the parents have a chance to devour them. 

Glofish Danio’s Mating Ritual 

You can encourage your danios to breed by feeding protein-rich food and performing a water change. The female will carry eggs in her belly for around 1-2 weeks before spawning. 

With danios, the mating process isn’t super detailed. They will chase and circle around each other. 

The female will then lay up to 400 eggs – 3 to 4 at a time, of course! 

As glofish danios are egg scatterers, the eggs won’t be laid in one single place. Instead, they’ll be laid on top of plants, decors, substrate, and so on. 

Once again, remove the parents immediately after they’re done spawning. 

The eggs will hatch within the next 36-48 hours. 

How To Breed Glofish Tetras?

pink and green glofish danio
Credit: Dennis Amith (CC License)

Breeding glofish tetras isn’t rocket science, but it’s not a piece of cake either. Since these fish scatter their eggs all over the place and then proceed to eat them, saving the eggs and growing them into adulthood can be a bit dicey. 

Like the regular black skirt tetras, glofish tetras don’t have the slightest parental instinct. 

Setting Up Your Glofish Tetra’s Breeding Tank

Since glofish tetras are pretty petite, a 10-gallon tank would be perfect for breeding. Using a bigger tank will only make it harder for the fry to find their food later. 

As usual, fully cycle the tank and ensure the new tank’s parameters are identical with the old one’s. Install a sponge filter so it doesn’t suck in the fry. 

For substrate, you can use marbles, artificial grass, or a spawning mop, so there’s a barrier between the parents and the eggs. Our goal is to make it as difficult as possible for the parents to reach the eggs once they’re laid and fertile. 

Glofish Tetra’s Breeding Ritual 

Female glofish tetras carry eggs for around 2 weeks. You can encourage spawning by feeding protein-rich live food and performing water changes in the meantime. 

The breeding ritual is nothing special or out of the ordinary. The male will chase and circle the female and occasionally quiver until she gives a green signal.

The female tetra will then lay 100-200 eggs over a few hours. 

Since glofish tetras are egg scatterers, the eggs will be spread all over the place. Once the male releases his milt and fertilizes the eggs, quickly remove both parents. 

Eggs will hatch in the next 36-48 hours. 

How To Breed Glofish Barbs?

Breeding glofish barbs is fairly easy – except for one small hiccup. They love to eat their own fry. Like rest of the glofish species, these barbs are also egg-layers and egg-scatterers. The female will deposit her eggs all over the place. And once the male is done fertilizing them, you quickly need to move the parents back into the main tank so they don’t feast on their own offspring. Yikes!

Setting Up Your Glofish Barb’s Breeding Tank

A tank sized 10 gallons would be enough for glofish barbs as these fish don’t grow very big. 

Once you fully cycle the tank and mimic the original tank’s water parameters, add plenty of plants and rocks that’ll serve as hiding places during bursts of anger. 

You can use marbles or artificial grass for substrate – basically anything that will prevent parents from devouring the eggs. 

Glofish Barb’s Mating Ritual 

A female barb’s gestation period lasts only for a couple of days. So, you don’t have to wait around for long. Feeding protein-rich food and carrying out a big water change will motivate them to spawn. 

The mating ritual usually starts in the late afternoon and will be over by the morning. 

The male will swim around the female and playfully chase her. He will even perform a headstand. Impressive!

The female will then lay around 300 eggs – 1 to 3 at a time. 

Therefore, it’s going to be a lengthy process. 

The male will then release his milt and externally fertilize the eggs. 

Since both parents will be eager to eat the eggs, you need to remove them immediately once they’re done spawning. 

The eggs will hatch in the next 36-48 hours.

How To Care For The Glofish Fry?

Glofish eggs ‘hatch’ in the next 36-48 hours after being laid. As a matter of fact, the eggs don’t hatch the same way a reptile or a bird’s egg does. 

Instead, the egg transforms and grows into different body parts. 

Once fully developed, the wigglers will rely on the nutritious yolk sac that comes attached to their body for much-needed nutrition. 

And once the sac is all drained and absorbed into their body, you need to manually feed them several times a day. 

Here’s a list of food they can eat:

  • Infusoria 
  • Baby brine shrimp
  • Pulverized flake food
  • Liquid fry food 
  • Egg yolk paste 

Since fry are pretty susceptible to starvation in their early days, it’s critical that you closely monitor their feeding habits. 

If they seem to avoid a certain kind of food, you need to quickly come up with an alternative. 

Besides that, ensure the tank isn’t too big for the fry. It will only make it challenging for the poor fellows to find their food. 

And for filtration, use a sponge filter that doesn’t suck in the little guys. 

Frequently Asked Questions 

Before we end this article, here are the answers to some of the most frequently asked questions. 

Do Glofish Breed In Captivity? 

Yes, glofish breed in captivity. As a matter of fact, glofish are captive-bred fish that aren’t found in the wild. Therefore, all the glofish you’ve seen and known were bred in captivity. 

What Do Glofish Tetra Eggs Look Like?

Glofish tetra eggs look like regular tetra eggs. They’re little spherical balls barely any bigger than one millimeter. As the eggs get fertilized and developed, you can see tiny dots inside the eggs, which are, in fact, eyes.

So, no – glofish eggs are neither colorful nor have a glowy appearance like their parents do. 

And this answer isn’t just applicable for glofish tetra eggs. It’s also relevant for the rest of the 4 glofish species’ eggs. 

If you are interested in watching some cool photos and videos of glofish eggs, you’ll want to check out this article

Pregnant Glofish? Is It Possible?

No, glofish cannot get pregnant. That term is only reserved for livebearers. However, glofish get gravid – meaning they carry eggs that will be laid in the future and fertilized by the male externally. 

If you’re interested to read up on the gestation period for each glofish species, the signs of a gravid glofish, taking care of the fry, and some more, you shouldn’t skip this info-loaded article. 

Final Words: How To Breed Glofish?

Here’s everything you need to know in a nutshell. 

First, ‘intentional’ breeding is illegal – so is any kind of unauthorized sales and barter. 

But if you glofish of both sexes present in the tank, there’s no way to stop nature from doing what it does the best – expand the lineage. Just make sure you don’t sell the little fry for quick money. 

Second, breeding glofish sharks is a rare feat that apparently hasn’t been achieved in home aquariums as of yet. So, there’s not much info available on that. 

I’ve been told that breeders use some special hormones to encourage these feisty fish to breed. 

The rest of the glofish species are egg-layers – also, egg-scatters. 

Not just that. They also have a good appetite for their own offspring. 

Therefore, you should remove the parents as soon as they’re done spawning. 

Recommended Readings!

Glofish Barb Care Guide | Diet, Habitat, Breeding, Accessories

Glofish Shark Care Guide | Diet, Habitat, Breeding, Accessories

Glofish Danio Care Guide | Diet, Habitat, Breeding, Accessories

Glofish Tetra Care Guide | Diet, Habitat, Breeding, Accessories

Glofish Betta Care Guide | Diet, Habitat, Breeding, Accessories

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.