How Big Do Glofish Tetras Get? Grow Them Fast!

Dec 30, 2021

How Big Do Glofish Tetras Get

There are two kinds of glofish tetras – regular and long-finned. In my experience, both are equally stunning to look at and easy to rear. In this blog, I’ll answer how big do glofish tetras get, their unique needs and also discuss if keeping them in small tanks can stunt their growth. 

Stay tuned! 

How Big Do Glofish Tetras Get?

Both the regular glofish tetra and long-finned glofish tetras are made by genetically modifying the pretty black skirt tetra. The standard glofish tetras grow around 2 inches (5 cm) long, whereas long-finned glofish tetras can reach around 2 ¼ inches (5.5 cm) long in captivity. 

How Fast Do Glofish Tetras Grow? 

Glofish tetras have a pretty decent lifespan. Therefore, they are not known to grow very quickly. For instance, they can take as long as 2 months to even reach ¼ inch in length. 

Usually, they will grow to their full-size potential within the first year, but late bloomers can take up to 2 years.

And although they do take their sweet time to grow, they will readily breed when they’re just 1 ½ inches long. 

What’s The Minimum Recommended Tank Size For Glofish Tetras?

Glofish tetras need at least 15 gallons to live happily and comfortably. 

I know 15 gallons seems too much when we’re used to seeing tetras confined in a 1.5 or 2-gallon tank. 

But hear me out. 

I’m not asking you to allocate 15 gallons for a single glofish tetra. 

These are schooling fish that should at least be kept in a group of 6. So, you’d require around 15 gallons for a school of 6 fish. 

And now that takes me to our next query. 

What Happens If Glofish Tetras Can’t School?

I might sound dramatic here, but if you deprive your glofish tetra of its innate instinct to school, the fish will become stressed, violent, as well as lose its appetite and potentially die. I wish I was kidding, but I’m not. 

When kept alone or in small numbers, schooling fish have a tendency to become depressed. 

The levels of stress hormones in their bodies increase, often leading to grave consequences like infertility, heart problems, weakened immunity, and stunted growth. 

And it’s not uncommon for a stressed and unhappy fish to die prematurely. 

Another complication that occurs when schooling fish are kept alone is increased aggression. 

Glofish tetras are reasonably peaceful and amicable when kept in suitably big groups. Otherwise, they become violent and nip at the fins of their tankmates. 

If you don’t have enough tank space to keep a sizable school of fish like glofish tetras, barbs, and danios, stick to fish that do well in their own company like glofish bettas and sharks. 

Recommended Readings!

What Do Glofish Eggs Look Like? Photos And Videos!

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

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

How To Grow Glofish Tetras Faster?

There’s no secret formula to growing any fish overnight. However, good fishkeeping practices like providing a big tank, feeding nutritious meals, and maintaining the water quality can definitely go a long way in ensuring your glofish tetras reach their maximum potential size in a short span. 

Let’s quickly go through them below. 

Providing A Big Tank 

Providing a bigger tank won’t magically help your glofish tetras grow faster. But keeping them in a small tank will definitely stunt their growth. Let me explain why. 

A small tank means your glofish tetras have less room to swim in and explore. It means your fish won’t get as much exercise as it needs. 

There will also inevitably be territorial disputes. This will severely stress out your tetras. The stress hormones in their body will increase, naturally hurting their health and growth. 

A small tank also means the water will get polluted easily. For instance, the same amount of leftover food in a small tank would pollute the tank a lot faster, while it’d get diluted and not cause much harm in a big tank. 

And lastly, studies have shown that fish release certain pheromones into the water, which discourages the growth of other fish of their own species. This wouldn’t pose a big problem in nature where these pheromones would get washed away instantly. 

However, in an enclosed system like a fish tank, we cannot rule out the possibility of these pheromones stunning your glofish betta’s growth. 

Feeding The Right Meal

Like any other fish, glofish tetras need a well-rounded and high-quality diet that ensures all the necessary nutrients to remain healthy and grow fast. 

Glofish tetras are omnivores. They readily accept a wide variety of food. However, you must zero in on quality pellets or flake food for their staple diet. 

Besides that, you can fortify their diet with delicious treats like bloodworms, daphnia, and brine shrimp. 

Ideally, you should feed your fish 2 to 3 times every day. Give them an amount they can consume within 2 minutes. 

Overfeeding will not cloud your water but also make the fish obese – potentially stunting their growth. 

Maintaining Water Quality 

Here’s what the ideal water parameters for glofish tetras look like:

  • Temperature: 70-80 degrees F
  • pH: 6.5-7.5
  • General hardness: 2-10 dGH
  • Ammonia: 0 PPM
  • Nitrite: 0 PPM 
  • Nitrate: Below 20 PPM

Maintaining the water quality directly doesn’t boost your glofish tetra’s growth, but it will make the fish happy, healthy, and stress-free. And these 3 definitely are growth boosters. 

A clean environment means your fish will be less susceptible to contracting infections and diseases. But, naturally, a diseased fish will not experience normal or healthy growth. 

Therefore, it’s essential to maintain the water parameters at all times. 

Here’s a quick rundown of things you should do daily, weekly, and monthly to clean the tank.

Daily Checklist 
  • Check the equipment 
  • Remove leftover food 
  • Top off the water level 

Weekly Checklist 
  • Perform tests
  • Wipe down the tank’s surfaces 
  • Shake off debris from plants and decor 
  • Scrape inside glass 
  • Siphon substrate 
  • Perform a partial water change 

Monthly Checklist 
  • Prune plants and deep clean decors 
  • Perform all tasks mentioned in the weekly checklist 
  • Change filter media 

Now that I think I have covered pretty much everything there’s to know on the subject, let’s get back to the basics. 

I’ll start with glofish tetra’s price! 

Glofish Tetra Price – How Much They Cost?

On the official glofish site, glofish tetras retail for $19.99 for a single fish. A basic assortment would cost you $54.99, whereas the deluxe collection is up for $69.99.

Glofish Tetra Behavior – What Is It Like?

Glofish tetras are well-mannered for the most part. When kept in a group of 6 or more, they will usually keep to themselves. However, occasional fighting, chasing, and nipping within the group are expected. 

However, if kept alone, glofish tetras are prone to being stressed, depressed, and agitated. 

Glofish Tetra Lifespan – How Long Do They Live?

Glofish tetras can live for around 3-5 years if properly cared for. However, the wrong diet and environment can cut their lives short easily. 

Glofish Tetra Temperature – What Do They Like?

Glofish tetras can sustain in temperatures between 60-80 degrees F. However, they’re most active between 70-80 degrees F. 

Glofish Tetra Feeding: What Do They Eat?

Glofish tetras are omnivores and super easy to feed. They will eat most kinds of flake food and pellets commercially available. You can then occasionally fortify their diet with food items like daphnia, brine shrimp, mealworms, and bloodworms. 

Breeding Glofish Tetras – Is It Legal?

Credits: Robert Kamalov (CC license)

According to glofish’s official website, it is illegal to ‘intentionally’ breed glofish. However, if you have male and female glofish in the same tank, they will inevitably spawn at some point. Just make sure that you don’t sell the offspring, so you don’t land in legal troubles! 

Glofish tetras can be difficult to breed because of their super-specific environmental needs. You will definitely need to set up a separate breeding tank with water hardness clocking at around 1 to 2 GH and pH maintained at around 5.0 to 6.0. The water temperature should fall between 72-75 degrees Fahrenheit. 

Equip it with a sponge filter and provide plenty of live plants. 

Performing a large water change and feeding live food rich in protein encourage breeding. 

The spawning will begin with the male embracing gravid female, who will then release over 100 eggs. The eggs are transparent, spherical, and slightly adhesive. They will stick to the plants. 

Once the eggs are fertilized, you need to immediately remove both parents from the tank since they’ll snack on their offspring with no hesitation. 

The eggs will ‘hatch’ within the next 24-48 hours. They will rely on the yolk sac for nutrition for the next couple of days. 

Unfortunately, the hatch rates aren’t very good. Therefore, don’t expect more than one-third of the eggs to yield viable fry. 

In the next 3-4 days, the fry will become free-swimming. After that, you can give them very pulverized or small foods like infusoria, rotifers, and egg yolk paste. 

Final Words: How Big Do Glofish Tetras Get?

Regular glofish tetras get around 2 inches (5 cm) long. As the moniker suggested, long-finned glofish tetras are a tad bit longer. They grow around 2 ¼ inches (5.5 cm) long. 

Both glofish varieties are developed from black skirt tetras. So, their size and rate of development are identical to the original species’. 

And while there’s no shortcut or formula to grow glofish tetras fast, creating the right environment and feeding the proper diet can definitely help them grow at the best rate nature allows! 

Recommended Readings!

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

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

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

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

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.