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Number of Glofish vs. Tank Gallon Size [Complete GUIDE]

Glofish are stunning, vibrant fish that will bring lots of excitement to your aquarium. However, being an aquarist, you should first have the ideal tank size sufficient for the movement and schooling of glofish.

Aquarists mostly get confused about how many Glofish can fit in a 10-Gallon tank. Different fish have distinct behavior related to the space they are provided. Your aquarium will develop into a healthy ecosystem, and your fish will have long and fulfilling lives if you make the right decisions.

The number of Glofish in a 10-gallon tank:

How many glofish in a 10-gallon tank? As highly active fish, five to six Glowfish can live in a 10-gallon tank. The fish will survive, but this tank size is not enough to make a happy environment. Maintaining water parameters in such a small tank is a tough job. The quantity of fish you can hold in an aquarium is determined by the type of glofish you choose. Depending on the size of the fish, a 10-gallon aquarium may hold three to six Glofish.

Having 15% fewer glofish in overcrowded tanks is favorable for avoiding conflicts and stress conditions.

Glofish size vs. quantity in a 10-Gallon Tank

Different kinds of glofish have different sizes. So diverse numbers of fish can be placed in a 10-Gallon; details are discussed in the following table.

Type of GlofishMaximum Size Quantity in 10-Gallon tank
Glofish Tetras2.5 inches4-5
Glofish Danios2.5 inches4-5
Glofish Tiger Barbs3 inches3-4
Glofish Rainbow Shark6 inches1-2 (10 gal not recommended)
Glofish size vs. quantity

The answer given above is not enough for such a broad topic.

Continue reading about how to make favorable conditions for your glofish, the male-to-female ratio in a single tank, adjusting your tank for multiple guppies, and much more.

Tank size vs. Number of Glofish Tetras

It is a peaceful kind of Glowfish; as mentioned earlier, it does not grow huge. The following table shows how many Glofish Tetras can be placed in different tank sizes.

Size of TankNo of Glofish Tetras
5 Gallons2-3
10 Gallons4-5
20 Gallons8-10
25 Gallons12-13
30 Gallons13-15
40 Gallons18-20
Size vs. No of Tetras

Tank size vs. Number of Glofish Danios

It is a peaceful kind of Glowfish; as mentioned above, it does not grow huge. The following table shows how many Glofish Danios can be placed in different tank sizes.

Size of TankNo of Glofish Danios
5 Gallons2-3
10 Gallons4-5
20 Gallons8-10
25 Gallons12-13
30 Gallons13-15
40 Gallons18-20
Tank size vs. No of Danios

Tank Size vs. No of Glofish Tiger Barbs

Tiger Barbs are mainly semi-aggressive and a little bigger than Tetra. It usually attacks the fries of Glofish Danios and Tetra. The following table shows how many Glofish Tiger Barbs can fit in different tank sizes.

Size of TankNo of Glofish Tiger Barbs
5 Gallons1-2
10 Gallons3-4
20 Gallons6-8
25 Gallons8-9
30 Gallons9-10
40 Gallons13-15
Size vs. No of Tiger Barbs

Tank Size vs. No of Glofish Rainbow Shark

Rainbow Sharks are aggressive and a little bigger than other species. It usually attacks their tank mates and damages their tails. Rainbow Shark is not recommended to be placed in a 10-gallon tank because of its size. The following table shows how many Rainbow Sharks can fit in different tank sizes.

Size of TankNo of Glofish Rainbow Shark
5 GallonsNot recommended
10 Gallons1-2 (Not recommended)
20 Gallons3
25 Gallons4
30 Gallons5
40 Gallons6-7
Tank Size vs. No of Rainbow Shark

People having space issues in their homes frequently ask, How many glofish in a 5-gallon tank? A detailed answer to this question is explained above. Stating it again:

Only 2 to 3 Tetra, Danio, or Tiger Barbs can live in a 5-gallon tank, but the environment won’t be happy, as they like to live in a community of a minimum of 4 to 5 fishes.

A 5-gallon tank is not recommended for a single Rainbow Shark because of its size.

I recommend using a large tank of more than 10 gallons if you are a glofish lover. Otherwise, Guppies or Bettas are best for a 5-gallon tank.

Here is the info about

Colors of Glofish

GloFish are similar to other fish, except they have much brighter colors. GloFish is available in six stunning colors, which are:

  • Starfire Red
  • Electric Green
  • Sunburst Orange
  • Cosmic Blue
  • Galactic Purple
  • Moonrise Pink

Do glofish eat each other?

Rainbow Shark glofish are aggressive. They chase and bully small glofish like Tetras and Danios. They eat and kill the small fish. A proper selection of glofish mates is necessary to keep your tank’s peaceful environment.

Which glofish can live together?

The following table shows the glofish species and their tank mates:

Glofish SpecieTank Mates
TetraGuppy, Betta, Danio, Rasbora, Cory Cats, and Angelfish
DanioGuppy, Betta, Tetra, Platy, Pleco, Swordtail, and Rasbora
Tiger BarbsGuppy, Gourami, Danio, Rainbowfish, Loach, and Molly
Rainbow SharkRainbow fish, Gourami, and Minnows
Extreme care is needed when introducing other Sharks
Glofish and its Tank Mates

Glofish chasing each other

Because of odd tank mates, territorial disputes, food conflicts, and baby protection, glofish chase each other, which may cause causalities.

Single glofish in a tank

Glofish are schooling fish. They prefer swimming and living in the form of a group. This way, they feel safer and less stressed.

Naturally, glofish of all types have little emotion about feeling isolated, but it does deteriorate their health compared to the guppies living in a group.

So I advise having glofish in your tank in a minimum group of five. (for that, of course, you will need a bigger tank, like a 10-gallon tank for Glofish Tetra and Danios, 40-gallons for Rainbow shark, and 30-gallons for Tiger Barbs.

Only male glofish living together in the 10-gallon tank

Male glofish have competing nature. They will constantly compete for food which will cause a fight among them.

Male glofish tend to hold territorial disputes. Therefore, to avoid an unfortunate environment, you should keep multiple female glofish with a single male glofish in your tank.

Taking care of the glofish in a 10-gallon tank

A 10-gallon tank is comparatively a large tank. So to keep your glofish alive and happy, you need to take good care of the tank/water parameters.

1. Plantation

Make sure you have enough plants in your tank to absorb the carbon dioxide, nitrate, and other substances that are toxic waste from the fish excretion.

Glofish can survive on their own with just plants and pests. So plantation in the ten-gallon tank is essential.

2. Water Quality Check

Change the water frequently to eliminate all the toxins. If you have a filter, change the water weekly.

If you do not have a water filter, about 40% of the tank water should be changed daily.

3. Water filter installation

You need a filter that will eliminate the ammonia by changing it to nitrite and then nitrite into a less toxic form called nitrate.

Nitrates are removed when you do the water changes in the tank. This process is called the Nitrogen Cycle.

4. PH Level

Also, make sure to maintain a healthy PH level in the tank. PH should be between 6-7. Here is how you can naturally control the PH in your water tank.

5. Water Temperature

Water temperature should be kept between 72 to 82 oF; a heater can also be placed in the tank to maintain the glofish likely temperature.