GloFish are genetically modified fish that glow under blacklight due to inserted genes from other organisms. They come in bright fluorescent colors like Starfire Red, Electric Green, Sunburst Orange, Cosmic Blue, and Galactic Purple. Many aquarium hobbyists are drawn to their unique, neon appearance and wonder if they can keep GloFish in a small 5-gallon tank.
Quick Answers
GloFish need a minimum tank size of 10 gallons. A 5-gallon tank is too small for any GloFish. While they are small fish, averaging 2 inches in length, they are active swimmers and produced a decent amount of waste. A 5-gallon does not provide adequate swimming space or water volume to dilute waste. GloFish will be stressed and unhealthy in a 5-gallon tank.
GloFish Tank Size
All GloFish species require a minimum 10 gallon tank despite their small size. This includes Starfire Red Danios, Electric Green Tetras, Cosmic Blue and Sunburst Orange Barbs, and Galactic Purple Tetras. The reasons a 5-gallon is unsuitable are:
- Lack of swimming room – GloFish are active swimmers and need horizontal swimming space. A 5-gallon is too narrow.
- Waste accumulation – These fish have a relatively high bio-load and need adequate water volume.
- Lack of hiding spots – GloFish need plants, rocks, driftwood to feel secure. No room for this in 5 gallons.
- Difficult water parameters – Such a small tank would see rapid fluctuations in ammonia, nitrite, pH that are unhealthy.
- Aggression issues – Some GloFish are nippy and need space from tankmates. No room to avoid aggression in 5 gallons.
The minimal 10 gallon size provides plenty of region for fish to swim vigorously, ample dilution of waste products, and space for decorations and plants to act as territories and visual barriers. It also allows water parameters to remain more stable.
GloFish Water Conditions
While GloFish are hardy, they do have some care requirements to thrive:
- Temperature 72-82°F
- pH 6.0-8.0
- KH 8-12
- GH 5-12
A small 5 gallon tank is prone to fast temperature swings beyond the preferred range. The pH can also shift rapidly with such little buffering capacity. The tiny volume also makes it challenging to maintain the ideal mineral levels for healthy osmoregulation. A 10+ gallon provides a more stable aquatic environment.
GloFish Tank Setup
A proper 10 gallon GloFish tank should include:
- Filter – Sponge, hang-on-back, canister or internal 10+ gallon filter
- Heater – Preset to 72-82°F
- Hood – With LED light for viewing fish
- Substrate – Smooth pebbles, sand, no sharp gravel
- Decor – Plants, rocks, driftwood for hiding spots
- No tankmates – Keep only GloFish in 10 gallons
The filter should turnover the tank volume at least 5 times per hour. This provides adequate biological filtration for waste breakdown. The heater keeps the water in the optimal thermal range. The hood contains bright lighting to make the fluorescent GloFish pop. The substrate should be soft and smooth to prevent injuring GloFish barbels if they root around. Plants, rocks and driftwood serve as territories and barriers, reducing aggressive nipping of long-finned varieties like Tetras. Avoid tankmates in a 10 gallon and keep only GloFish.
Suitable GloFish for 10 Gallon Tanks
These GloFish species are suitable for a 10 gallon tank if kept singly:
| GloFish Type | Size | Recommended Number |
|---|---|---|
| Starfire Red Danio | 2 inches | 6 Danios |
| Electric Green Tetra | 1.5 inches | 6 Tetras |
| Sunburst Orange Barb | 2 inches | 5 Barbs |
| Cosmic Blue Barb | 2 inches | 5 Barbs |
| Galactic Purple Tetra | 1.5 inches | 6 Tetras |
A group of 6 Danios, 6 Tetras, or 5 Barbs is recommended in a 10 gallon tank. Mixing species is not ideal given potential fin nipping issues. The small tank size limits options, so best to keep one GloFish species schools. Perform regular partial water changes and monitor water parameters.
Caring for GloFish in 10 Gallons
Caring for GloFish in a proper 10+ gallon tank includes:
- 25% weekly water change
- Testing water 1-2 times per month
- Feeding 1-2 times daily
- Not overstocking
- Quarantining new fish
- Using air stone for oxygenation
- Cleaning tank and filter monthly
Weekly 25% water changes are key to resetting nutrient levels and preventing waste buildup. Test for ammonia, nitrite, nitrate and pH periodically to ensure water quality. Feed a high quality tropical flake, pellet or crisps once or twice a day. Resist overstocking by following above guidelines. Quarantine new fish for 2-4 weeks to prevent disease transmission. An air stone adds surface agitation and extra oxygen. Monthly tank scrubbing and filter rinsing keeps things clean.
10 Gallon GloFish Tank Mates
No tankmates are recommended with GloFish in a 10 gallon aquarium. The limited space increases aggression and nipping potential. Suitable companions in larger tanks include:
- White Cloud Minnows
- Harlequin Rasboras
- Ember Tetras
- Habrosus Corydoras
- Nerite Snails
- Amano Shrimp
- Ghost Shrimp
Minnows, Rasboras, Ember Tetras, small Cory Cats, and invertebrates like snails and shrimp make good tankmates in a 20 gallon or larger aquarium. They have similar water parameter needs as GloFish. But avoid mixing species in constrained 10 gallon tanks.
Converting 5 Gallon to GloFish Tank
If you already have a 5 gallon aquarium, consider these alternative fish species choices:
- Betta Fish
- African Dwarf Frogs
- Endler’s Livebearers
- Ember Tetras
- Least Killifish
A single male Betta makes a nice centerpiece fish for a 5 gallon. African Dwarf Frogs only get 1-1.5 inches long and do well in a small tank. Endler’s Livebearers remain under 2 inches and are very active. A small school of 6 Ember Tetras or Least Killifish work with adequate filtration. Make sure to research proper care for any species you consider.
Planted GloFish Tank
Live plants offer many benefits in a GloFish aquarium. They help control waste, absorb nitrogen compounds, provide shade, and release oxygen. Some easy, low-light options include:
- Java Fern
- Java Moss
- Anubias
- Cryptocorynes
- Amazon Sword
- Water Wisteria
- Hornwort
- Anacharis
These adaptable plants tolerate the warm tropical temperatures preferred by GloFish. Floating plants like Hornwort also diffuse light and offer cover. For a planted tank, use a quality substrate and provide supplemental fertilization with root tabs and liquid fertilizers.
Conclusion
Keeping GloFish in a 5-gallon tank is inadvisable given their activity level and waste output. A minimum 10 gallon tank provides the needed swimming area, horizontal space, and water volume for a healthy GloFish environment. Carefully research and follow the specific requirements for tank size, water parameters, diet, tankmates, and tank setup before getting GloFish. This ensures your fluorescent beauties thrive and exhibit their unnatural neon colors for years to come in a properly sized and maintained home!
